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Tracing Historical Influences of Lean Six Sigma 1

Running head: TRACING HISTORICAL INFLUENCES OF LEAN SIX SIGMA

The Evolution of Quality Management: Tracing Historical Influences of Lean Six Sigma

Scott Thor


Abstract

The evolution of quality management has changed dramatically in the past decade. Once looked

upon as only a function for finding defective product, the role of quality in modern organizations

has transformed into a proactive role centered on prevention and improvement initiatives.

Several key individuals such as Taylor, Ford, Shewhart, Deming, and Ohno have contributed to

the quality movement, leading to the most contemporary methodology known as Lean Six

Sigma. Lean was born out of the Toyota Production System (TPS) and gained widespread

popularity as the Japanese successfully challenged U.S. automakers during the 1980s. Six Sigma

was developed at Motorola in the 1980s and targets reducing variation within processes. In

recent times Lean and Six Sigma have been combined to form an improvement methodology that

offers the full spectrum of quality improvement tools for both simple and complex problems.

This paper describes the evolution of quality management and provides a detailed overview of

Lean, Six Sigma, and their eventual combining. The paper also provides a historical background

of the individuals who have influenced the quality movement. Also provided within the paper are

both the positive and negative aspects of Lean Six Sigma. The paper concludes with a look to

what the future holds for Lean Six Sigma.


The Evolution of Quality Management

Quality management has significantly evolved over the last several decades. In a

traditional sense, the role of quality was initially developed as a mechanism for ensuring control

over the output of a process (Addey, 2004). The role of quality was to find defective product

before it reached the customer, which placed the quality function in a position of policing an

organization’s products (Chen, Coccari, Paetsch, & Paulraj, 2000).

Deming (2000) popularized the notion that quality comes not from inspection, but

improvement of the process, which led to a paradigm shift in quality management in the 1980s.

Deming helped move industry from quality control activities being the primary role of quality, to

one of quality assurance, where focus is placed on prevention instead of detection. As the quality

function started to evolve from detection to prevention, continual improvement began to take

hold in the quality profession with the rise in popularity of international quality standards, most

notably ISO 9000, and the concept of total quality management (TQM).

The ISO 9001 standard gained popularity in the 1990s to help satisfy the need for an

international standard for quality management systems (Okes & Westcott, 2001). The

widespread acceptance of the ISO standard expanded the scope of quality management toward a

focus of compliance with the standard, and continual improvement initiatives aimed at

improving organizational processes.

The concept of TQM is best summarized as a management system focused on customer

satisfaction that involves all employees of an organization in continual improvement activities

(Okes & Westcott, 2001). With a greater focus on improvement emphasized by the ISO standard,

TQM became a complimentary addition to the responsibilities of quality leaders in the 1990s,

elevating their value in organizations striving to compete globally.


Building on the concept of continual improvement grounded in the ISO standards and

TQM, Lean and Six Sigma evolved from the need to reduce non-value added activities, and

minimize variation, respectively. The concept behind Lean came from the Japanese automakers

that gained significant market share over U.S. automakers in the 1970s and 1980s (Womack,

Jones, & Roos, 1990). The primary objective of Lean is centered on improving efficiency by

removing waste (Jing, 2009). Lean thinking suggests that by minimizing or eliminating non-

value activities, which are activities customers are unwilling to pay for, an organization can

deliver products and services quicker and at a lower cost with higher quality (Womack et al.).

In the last decade Six Sigma has gained popularity because of the bottom line financial

results the process focuses on (Eckes, 2001; Hahn, Hill, Hoerl, & Zinkgraf, 1999). The raw

statistics of Six Sigma equate to 3.4 defects per million opportunities, nearly a perfect level of

quality. The central focus of Six Sigma is based in the idea that quality is defined as meeting

customer expectations with minimal variation. The process of Six Sigma can generally be

described as defining and measuring the problem, analyzing data, establishing improvement

initiatives, and implementing control mechanisms to maintain the improvements (Harry, 2000).

The most recent advancement in quality management has been the combining of Lean

and Six Sigma. Lean Six Sigma brings together the focus of Lean in reducing non-value added

activities, and the fact-based approach of Six Sigma centered on data driven process

improvement. Jing (2009) describes Lean Six Sigma as, “an improvement program or approach

aimed at combining both Lean and Six Sigma to improve efficiency and capability primarily by

removing wastes and variation” (p. 26). George, Rowlands, and Kastle (2004) describe Lean Six

Sigma as having two key aspects that include delighting customers and improving processes.

Delighting customers comes from providing a quality product or service quickly, taking


advantage of the Lean aspects of Lean Six Sigma. Improving processes comes from reducing

variation and defects, a key component to Six Sigma, and improving process flow. Both

delighting customers and improving processes are based on data and facts. Lean Six Sigma

represents not only an improvement methodology, but also the most recent advancement in the

evolution of quality management.

This paper seeks to trace the evolution of quality management that has led to the

development of Lean Six Sigma. The paper describes in detail the key elements of TQM, Six

Sigma, and Lean, and provides a historical overview of each methodology leading to the

development of Lean Six Sigma. Also discussed are the early pioneers who influenced the

concept of quality improvement and how their work led to the modern techniques utilized in

Lean Six Sigma. The paper also describes the challenges to Lean Six Sigma and some of the

positive and negative aspects in utilizing the process. The paper concludes with a discussion on

the future of Lean Six Sigma, and whether the process will continue to develop or be written off

as another management fad.

Definition of Terms

5S: A key aspect to Lean that drives the organization of work spaces to increase efficiency and

eliminate unnecessary clutter. The five S’s include sorting, straightening or setting in order,

sweeping or shining, standardizing, and sustaining the discipline. Some organizations also

include a sixth s that includes safety.

Common Causes: These types of causes of variation within a process are inherent in the process.

A process with only common cause variation is considered to be in a state of control.

Control Chart: A chart used to plot the output of a process over a period of time. This type of

chart can be used to plot both variable and attribute data.


FMEA: This tool is utilized to define and rank potential failure modes of a process or design.

Failure mode and effects analysis is completed to help establish proactive efforts where serious

failure may occur.

Kaizen: An event typically lasting from a few hours to a few days where teams of individuals

come together and implement an improvement project.

Kanban: This is a tool used to establish a pull system of production. A kanban card is typically

used to signal an upstream process that more product is needed to continue downstream

processes. The goal of kanban is minimizing the amount of work in process.

Pareto Chart: A chart used to rank the frequency of a problem from the highest recurring to the

least. These charts aid in identifying where to focus improvement efforts.

Scatter Plot: This type of data plot is commonly used to visualize correlations between two or

more variables.

SIPOC Diagram: This type of diagram helps in understanding the key components in a value

stream. The diagram defines suppliers, inputs, processes, outputs, and customers.

SMED: Single minute exchange of dies is a concept utilized in Lean to rapidly change from one

product to another with minimal change over time.

Special Causes: Unlike common causes, special causes are unique causes to variation within a

process. These types of causes can always be assigned to a change in the process.

Value Stream Map: This is one of the most common tools utilized in Lean. The map establishes a

current state to aid in understanding where opportunity to improve exists. The map is also a key

tool in understanding the sources of waste in the process.

Six Sigma and TQM


Six Sigma began at Motorola in the 1980s and has since gained widespread popularity in

the business media based on its success at large organizations such as General Electric and

Allied Signal (Mader, 2008; Pande, Neuman, & Cavanagh, 2000; Shah, Chandrasekaran, &

Linderman, 2008). The six generally accepted aspects related to Six Sigma include:

1. Top management leadership

2. A focus on customer requirements

3. Focus on financial and non-financial results

4. Use of a structured method of process improvement

5. Strategic project selection

6. Full-time specialists (Schroeder, Linderman, Liedtke, & Choo, 2008)

Traditional definitions of quality have focused on meeting tolerances or staying within

specification limits. Six Sigma differs from the traditional viewpoint of quality in that Six

Sigma’s focus is not only on meeting specifications, but also reducing variation. Six Sigma has

been compared to TQM, which gained popularity in the 1980s.

TQM programs were introduced to U.S. organizations in response to the competitive

onslaught of Japanese companies in the electronics and automotive sectors (Beer, 2003).

American organizations had no other choice but to improve their quality management systems to

keep up with the high quality products coming from Japan. TQM, much like Six Sigma in the

late 1990s, was the latest fad on many executive management teams’ agendas, hoping it would

be the answer to all their problems.

Several definitions and descriptions of TQM exist. Gopal, Kristensen, and Dahlgaard

(1995) define TQM as an improvement initiative based on four governing principles:

• Delight the customer


• Management by facts

• People-based management

• Continuous improvement

Each principle can be used to drive improvement on its own, but the real power of TQM

is found in combining each of the principles, building on one another. TQM’s primary focus is

customer satisfaction and continual improvement, which has some similarities to Six Sigma.

Where the two methodologies differ is that Six Sigma takes process improvement a step further

and has an added focus on fact-based problem solving, and a direct link to financial results. One

could argue that Six Sigma is the next evolution of TQM.

The statistical definition of Six Sigma is 3.4 defects per million opportunities, but Six

Sigma is more than just a number. Six Sigma is a way of conducting business and creating a

culture focused on continual improvement. Several authors, researchers, and academics have

defined Six Sigma in the following ways:

• Harry and Schroeder (2000), two of the initial developers of Six Sigma, define Six

Sigma as a process to significantly improve financial performance through process

design and monitoring that reduces waste and resources, and increases customer

satisfaction.

• Pande et al. (2000) describe Six Sigma as a method that combines the best current

techniques with those of the past to reduce defects to near zero, and reduce variation

to minimize standard deviations so that products and services meet or exceed

customer expectations.


• Snee and Hoerl (2003) define Six Sigma as a holistic strategy and methodology for

improving business performance, integrating proven performance improvement tools

to increase customer satisfaction and financial results.

The heart of Six Sigma lies in the DMAIC methodology, which consists of the processes

of define, measure, analyze, improve, and control (Brewer & Eighme, 2005). The first step in the

process is defining the problem. With the problem defined, the next task is measuring the size of

the problem, followed by analyzing the collected data, then making improvements to the process,

and finally implementing controls to maintain the improvements. The primary outcome Six

Sigma projects strive for is the reduction of variation within a process. Many of the statistical

tools utilized in the Six Sigma process have been around for many years (Naumann &

Hoisington, 2001). Such tools as process capability, statistical process control, and error proofing

are commonly used in Six Sigma to understand and control variation (Shah et al., 2008). Experts

typically lead Six Sigma projects with varying degrees of knowledge in statistical analysis. These

improvement specialists are most commonly categorized as master black belts, black belts, and

green belts (Bertels, 2003). Master black belts are at the top of the expertise hierarchy and

generally mentor black and green belts, develop and conduct training sessions, and lead in the

selection of projects. Black belts primarily act as project managers, leading projects and guiding

green belts that are tasked with project oriented activities such as data collection and

implementation of improvements and controls.

An argument can be made that the concepts and ideas Six Sigma focuses on are really

nothing new, and that Six Sigma only combines existing quality improvement tools into a

structured approach to process improvement. What is unique to Six Sigma is its focus on bottom

line results, which appeals to senior leaders (Evans & Lindsay, 2005). Previous quality


improvement methodologies have had mixed results in relation to financial improvement

(Fuchsberg, 1992; Powell, 1995). Many organizations utilizing Six Sigma also employ

accounting professionals tasked with quantifying the results of improvement projects (Pyzdek,

2003), which distinguishes Six Sigma from previous quality improvement methodologies

(Bertels, 2003; Pande et. al, 2000). Whether or not Six Sigma has greater staying power than

previous quality improvement techniques is yet to be determined, but one thing is certain, if

organizations continue to realize financial savings based on Six Sigma the probability of its

success is sure to increase.

Lean Thinking

Lean can both be described as a philosophy and also a system, both of which focus on the

elimination of waste. Several types of waste exist and can include overproduction, waiting time,

product movement, the processing of product, unneeded inventory, unnecessary motion, and

scrap (Ohno, 1988). Lean evolved out of the Toyota Production System (TPS) throughout the

course of several decades (Shah et al., 2008). Researchers studying the automotive industry at

MIT in the late 1980s coined the term “lean” (Womack et al., 1990, p. 13) to describe TPS

because it generally uses less of everything when compared to mass production. Womack et al.

define Lean as a production and business philosophy that reduces the time between order

placement and the delivery of a product by reducing the amount of waste in a product’s value

stream. Womack and Jones (1996) build upon their original work at MIT to expand Lean as a

way of thinking. The authors argue that Lean thinking consists of five key principles that

include:

1. Value

2. The value stream


3. Flow

4. Pull

5. Perfection

Lean thinking begins by defining value in relation to specific products with specific

capabilities priced specifically through a dialogue with specific customers (Womack & Jones,

1996). To truly understand where waste exists organizations must know what customers value.

Understanding the value stream is the next phase of Lean thinking. Womack and Jones define the

value stream as:

The set of all the specific actions required to bring a specific product (whether a

good, a service, or, increasingly, a combination of the two) through the three

critical management tasks of any business: the problem-solving task running from

concept through detailed design and engineering to production launch, the

information management task running from order-taking through detailed

scheduling to delivery, and the physical transformation task proceeding from raw

materials to a finished product in the hands of the customer. (p. 19)

A value stream map, similar to a process flow diagram, is commonly used to illustrate the

value stream with the primary goal of understanding where waste within the stream exists. The

next step in the process, flow, is where the real breakthrough happens (Womack & Jones, 1996).

With a clear understanding of value and the elimination of wasteful processes within the value

stream, the focus turns to improving the flow of product and/or services through the value stream

as quickly as possible. This can be one of the most challenging aspects of Lean because of the

typical function and department mindset most people within an organization have. To truly


create flow Womack and Jones argue that organizations need to redefine the work of employees

so they can contribute to the process of creating value.

To create flow Womack and Jones (1996) believe a new way of looking at the whole

organization is necessary. They call this perspective the Lean enterprise, which begins by

specifying value uniformly throughout the organization, and defining actions needed to bring

product from launch to the customer and on through its useful life. With these actions complete,

the next step becomes removing those actions that do not create value, and making those that do

flow as pulled by the customer, which leads to the fourth principle of lean thinking.

One way to describe pull is from the viewpoint of the customer. The customer can be

either an internal process contained within the value stream or an external user of a product or

service. Unlike traditional mass production where product is pushed to the next process in large

quantities, the concept of pull in Lean thinking is that product should be produced at the rate of

which the next process, be it an internal user or the external customer, demands it. The primary

benefit from going to a pull system versus a push system is the time it takes to go from product

concept to delivery to the customer decreases dramatically (Womack & Jones, 1996). A

secondary benefit to pull is that a significant decrease in inventory is created, which also

increases the levels of cash once invested in raw materials and work in process that can now be

invested in other value creating activities. The final principle in Lean thinking is perfection,

which initiates the continual improvement process by starting the cycle over and constantly

striving for improvement. Lean thinking is a perpetual cycle that continues until there is no waste

left within the system.

Unlike Six Sigma, which has a high degree of technical expertise required for success,

Lean is considered to require a much lower level of competency (Jing, 2009). Most of the tools


utilized in implementing Lean are intuitive and require minimal amounts of specialized training.

The primary tools used in Lean consist of value stream mapping, 5S, Kaizen, one-piece flow,

cellular manufacturing, Poka Yoke, standardized work, and total productive maintenance

(Upadhye, Deshmukh, & Garg, 2010).

A value stream map, mentioned previously, is the primary tool utilized to illustrate the

value stream to aid in understanding where value is created and waste exists (Womack & Jones,

1996). 5S is a method that can be used to remove waste associated with disorganization of a

work environment (Hirano, 1995). Kaizen is the process of continually implementing small

improvement projects focused on removing waste (Cheng & Podolsky, 1996). One-piece flow is

a concept that minimizes work in process, which results in reduced inventories, decreases the

amount of material handling, and provides quick feedback when a quality problem arises

(Sekine, 1992).

Cellular manufacturing aims at grouping machines together that produce parts for a

similar product to aid in the one-piece flow process (Upadhye, et al., 2010). Poka Yoke focuses

on error proofing processes to avoid mistakes. Some typical Poka Yoke devices include guide

pins, error detection alarms, counters, limit switches, and checklists (Shingo, 1989).

Standardized work establishes best practices based on the best-known sequences using the

available resources. A job is broken down into individual steps to determine the most efficient

process, which are then used to establish a standard that is taught and sustained through

repetition (Jadhav & Khire, 2007). A final key tool utilized in Lean is total productive

maintenance (TPM). TPM is an extension of preventive maintenance that involves the operators

in the process of maintaining the equipment they utilize (Nakajima, 1988).


Where Six Sigma is an easily quantifiable approach to improvement, it can create an

overly complex time consuming method to solving simple problems. Likewise, the subjective

nature the Lean tools utilize make it harder to quantify the level of improvements, but the

methodology is arguably easier to implement for quicker results. Until recently the

methodologies were looked upon as two different approaches for organizational improvement.

Only in recent times have the two been combined, creating the next level of quality improvement

that offers both quantitative statistically based results when necessary, and rapid less complex

initiatives when the need is focused more on simple improvement projects.

Lean Six Sigma

Lean and Six Sigma can be characterized by their philosophies, methodology of the tools

utilized to implement them, degree of difficulty, duration for a typical initiative, and the level of

training and timeframe for implementation. Table 1 summarizes a comparison of Lean and Six

Sigma. Both Lean and Six Sigma have a number of similarities and differences.

The most significant similarity between the methodologies is their focus on quality

management (Shah et al., 2008). Advocates of Lean quite often suggest the use of process

capability and statistical process control when defining Lean (McLachlin, 1997; Shah & Ward,

2003). Advocates of Six Sigma, similarly, emphasize quality management through the use of

statistical analysis, which is considered to be the foundation of Six Sigma (Evans & Lindsay,

2005; George, 2002).

Shah et al. (2008) suggest several differences between the methodologies. Six Sigma

tends to focus more on invisible problems such as variation within a process, whereas Lean tends

to center on problems that are visible such as process flow. Lean is also typically more of a

bottom up approach that has a high degree of involvement from production level employees


unlike Six Sigma, which more frequently is driven by projects selected by senior management.

The level of expertise or specialization is also significantly higher with Six Sigma due to the

heavy statistical emphasis versus Lean, which takes a more practical approach that is more easily

understood.

Table 1

Comparison of Lean and Six Sigma

Lean Six Sigma

Key focus Eliminating waste Reducing variation

Methodology Specify value, identify the value

stream, flow, pull, pursue perfection

Define, measure, analyze, improve,

control

Tools Value stream maps, 5S, Kaizen

events, SMED, Kanban, work cells

Control charts, process flows,

SIPOC diagrams, scatter plots,

Pareto charts

Difficulty Low, mostly common sense

approach, qualitative, subjective

approach

High, heavy emphasis on statistics,

quantitative, fact-based approach

Typical initiative

duration

Event focused, small incremental

improvement through quick Kaizen

events, days to weeks

Project focused, structured

approach, typically span several

months

Training and

implementation

Low complexity training and quick

implementation

High complexity training, multiple

expertise levels (belts), slow

implementation


One could argue that Lean and Six Sigma when combined represent a methodology of

quality improvement that offers the best of both ends of the process improvement spectrum. On

one end of the spectrum Lean offers a pragmatic approach that is quick to implement, and is

readily grasped by employees with little understanding in advanced data analysis techniques. On

the other end of the spectrum Six Sigma provides a data rich methodology when problems are

less visible and require more rigorous methods to understand how to improve the process. An

argument could also be made that quality professionals trained in both methods will yield higher

returns than those trained in only one of the methods.

Snee and Hoerl (2007) argue that Lean Six Sigma offers a holistic approach to quality

improvement that is needed to make long-term gains in performance. The authors suggest that by

combining Lean and Six Sigma organizations will be able to more easily create a culture of

improvement. Snee and Hoerl also suggest that utilizing a holistic approach to improvement,

such as Lean Six Sigma, represents the opportunity to reduce costs, improve quality, and

increase the speed of delivery anywhere within an organization throughout the world.

Historical Roots of Lean Six Sigma

Despite Lean Six Sigma being a relatively new quality improvement technique, one could

argue much of the foundation upon which Lean Six Sigma is based is grounded in the work of

individuals dating back to the early 1900s (see Appendix A for a detailed timeline). Taylor’s

scientific management, Ford’s creation of the production line, Shewhart’s concept of statistical

quality control, Deming’s seven deadly sins and diseases, and the work done by Ohno in the

development of the Toyota Production System have all influenced the principles upon which

Lean Six Sigma is based.

Frederick Taylor- Scientific Management


In the first part of the twentieth century Fredrick Winslow Taylor developed what he

called scientific management. During this time period Taylor began an effort to divide labor,

leading to the creation of scientific management. Taylor is best known for his research on

studying workers and doing time and motion studies, which were used to increase efficiency in

the workplace. Taylor’s (1916) scientific management consists of four key elements:

1. Gathering of knowledge about the work (time and motion studies)

2. Selection of the workman

3. Bringing of the workman and the science together

4. Division of work

The knowledge Taylor spoke of gathering began by studying workers and breaking down

the work they were doing into its simplest form. Time and motion studies were also conducted to

understand the duration for a particular task to be completed. The first element gave Taylor the

basis for improvement by providing a baseline of performance. With an understanding of the

work, Taylor believed the selection of the workman was of great importance to achieving

maximum efficiency. He believed it was management’s job to select the workers best suited for

the work. If workers were not matched with the jobs they were doing Taylor believed

productivity would suffer.

The third element of scientific management consists of bringing the worker and science

together. Without bringing the two together companies using the scientific management

principles could not realize the benefits they offered. In order to bring the two together Taylor

(1916) suggested management should offer the workman something he felt was worthwhile for

working under the conditions, essentially an incentive to make the workman want to work under

the scientific management principles. The final aspect of scientific management is the division of


work. As Taylor described, under the old system of management the workman did most of the

work, but with the new system work was divided into two parts. One component of the work was

now given to management, leaving the other for the workman. Taylor argued by dividing the

work it created an atmosphere of teamwork between management and the workman because

each group was dependant on the other. Taylor’s work benefited the workman greatly, increasing

his earnings and also lowering the cost of goods produced.

A link to Taylor’s work can be seen in several Lean Six Sigma tools, most notably, the

concept of standardized work and value stream mapping. By breaking down the key steps in the

process Taylor laid the foundation for understanding where wasted motion exists. By eliminating

the wasted efforts Taylor established the one best way that mimics the modern concept of

standardized work.

Henry Ford-The Production Line

During the same time Taylor was implementing his concept of scientific management at

organizations across the U.S., Henry Ford was bringing the automobile to the mass market by

driving down the cost of manufacturing through the use of the production line. From 1909 to

1919 Ford was able to reduce the number of hours to produce a Model T by over two-thirds

(Williams, Haslam, & Williams, 1992). Several ideas utilized by Ford have links to the modern

Lean movement such as work cell design and just in time inventory control.

Ford (1922) believed workers who are undirected spend more time walking around

looking for materials and tools, which leads to lower output. This thought led to his development

of the production line, which is still in use today, and also has similarities to the concept of the

work cells utilized in Lean. In creating the production line Ford believed the work should be

brought to the man instead of the man looking for the work. Ford writes, “We now have two


general principles in all operations-that a man shall never have to take more than one step, if

possibly it can be avoided, and that no man need ever stoop over” (p. 80). Ford goes on to

describe the principles of assembly as placing men and tools as close to the product as possible,

also helping to reduce the distance which product needs to move through the process, and

minimizing the motion required by each man to complete a process.

Ford (1922) also influenced the concept of just in time inventory control. Ford writes,

“We have found in buying materials that it is not worth while to buy for other than immediate

needs. We buy only enough to fit into the plan of production” (p. 143). Ford goes on to say, “But

we have found that thus buying ahead does not pay” (p. 144). Clearly, Ford understood that

managing inventory levels and delivering materials as they were needed led to improved

performance.

Walter Shewhart-Statistical Quality Control and the PDCA Cycle

Walter Shewhart is widely considered the father of statistical quality control (Okes &

Westcott, 2001). Much of his career was spent at Bell Laboratories working as part of the

technical staff. His key contributions include the development of the control chart and the

Shewhart cycle. He also spent time working for Western Electric with W. Edwards Deming,

whom he greatly influenced. Eventually, the Shewhart cycle would later become better known as

the Deming cycle because of Deming’s influence on Japanese industry (Wheeler & Chambers,

1992).

Shewhart (1980) created the control chart during his time at Bell Labs in the 1920s for

plotting data from a process to better identify the sources of variation. Shewhart describes

variation as coming from either chance or assignable causes. Chance causes, Shewhart argues,

are naturally part of the process. To reduce this type of variation the process itself must be


improved. Processes with only chance causes are considered to be in an ideal state and producing

only product within specification (Wheeler & Chambers, 1992). Shewhart believes that a second

type of variation comes from assignable causes, which can be identified and eliminated.

Shewhart’s work in developing the control chart has played a pivotal role in Six Sigma by

helping understand the variation within a process, the foundation upon which Six Sigma is based.

Figure 1. Shewhart PDCA cycle. This figure illustrates the Shewhart plan, do, check, act cycle.

Another contribution Shewhart made to the foundation upon quality improvement is the

plan, do, check, act cycle illustrated in Figure 1. An argument can be made that all process

improvement initiatives follow a similar path. The Six Sigma DMAIC methodology previously

mentioned has similarities to the Shewhart cycle. Defining the problem can be looked upon as a

plan, measuring and analyzing have similar characteristics as the do and check phases, and

improving and controlling can be viewed as the process of acting. Likewise, the Lean thinking

principle of perfection carries similar meaning to the cycle in that it is a constant improvement

process that never ends.

W. Edwards Deming-Seven Deadly Sins and Diseases and a System of Profound Knowledge

Plan

Do

Check

Act


W. Edwards Deming has arguably been the most influential individual related to all

aspects of quality control, assurance, and management. Deming spent much of his career helping

Japanese industry recover after World War II, but gained little recognition in the U.S. until the

1980s. Deming’s contribution touches both Lean and Six Sigma. Deming understood the

importance of controlling variation stating, “If I had to reduce my message for management to

just a few words, I’d say it all had to do with reducing variation” (Neave, 1990, p. 57).

Deming (2000) defines his theory of management as the seven deadly sins and diseases,

which consist of the following:

• Lack of constancy

• Short-term profit focus

• Performance appraisals

• Job-hopping

• Use of visible figures only

• Excessive medical costs

• Excessive costs of liability

Creating a constancy of purpose suggests that an organization must define its purpose and

the values the organization believes in. Deming (2000) also believes many organizations place

too great an emphasis on short-term profitability instead of long- term survival. Adding to this

argument, Deming believes that performance appraisals add to the short-term focus issue and

only promote individuality instead of teamwork. Changing jobs frequently also creates focus on

only the short-term, according to Deming. Using only visible figures is also a disease Deming

believes organizations have. Not all measures of success can be quantified, according to Deming,

although this does conflict to some degree with his view that a quantitative approach will yield


the best results. Deming’s belief related to excessive medical and liability costs were truly ahead

of his time, and add to his long-term viewpoint that is now coming to fruition as healthcare and

litigation costs are a reality for all organizations.

Perhaps Deming’s most significant contribution to Lean and Six Sigma is his notion of a

system of profound knowledge. This system consists of four components that include knowledge

about the system, some knowledge about variation, some theory of knowledge, and some

psychology (Neave, 1990). Deming understood the idea behind systems and how they

interconnect with one another and the affect variation can have on the system, both of which are

key to Lean thinking and Six Sigma.

Summarizing Deming’s key contributions to Lean and Six Sigma they include utilizing a

quantitative process that is statistically valid and employs a methodical approach, and the notion

of continual improvement. Although Deming did not contribute a specific methodology to be

followed, an argument can be made that his ideas are found in the core elements of Lean and Six

Sigma.

Taiichi Ohno-Toyota Production System

Taiichi Ohno is widely considered one of the fathers of the Toyota Production System

(TPS) (Liker, 2004). Ohno spent his entire career working at Toyota developing TPS. Ohno

(1988) argues that the preliminary step before implementing TPS is to first identify the sources

of waste, or what he commonly refers to as muda (the Japanese word for waste). Ohno suggests

there are seven types of waste that include:

• Waste of overproduction

• Waste of time on hand (waiting)

• Waste in transportation


• Waste of processing itself

• Waste of stock on hand (inventory)

• Waste of movement

• Waste of making defective products (p. 19-20)

Ohno argues (1988) that by eliminating waste within the process a product can be

delivered to a customer faster, with higher quality, and lower costs. Ohno is also credited in

developing just in time inventory through the use of Kanban. The concept underlying Kanban

means signboard or billboard, which are used to signal a process feeding another when more

material is needed. The Lean thinking principle of pull, as discussed earlier, is based in the idea

behind Kanban. In traditional mass production large batches are pushed to downstream

operations, creating waste in the form of over production and unnecessary inventory. Ohno

realized by using Kanban cards upstream processes could supply downstream processes at a rate

in which they consume product, creating a just in time system with minimal inventory or work in

process.

Ohno (1988) was also instrumental in developing what has become known as the 5 why

problem solving method. This method of problem solving asks the question of why a problem

exists five times to better understand the root cause(s) of the problem so that solutions can be

implemented. Ohno also focused on developing teamwork between workers passing product off

to one another. Ohno summarizes TPS as, “All we are doing is looking at the time line from the

moment the customer gives us an order to the point when we collect the cash. And we are

reducing that time line by removing the non-value-added wastes” (p. ix). Looking back on

Ohno’s work an argument can easily be made that he was the driving force in what is now

known as Lean.


Challenges and Benefits of Lean Six Sigma

Lean Six Sigma has the ability, when implemented effectively, to transform

organizational cultures into continual improvement environments constantly focused on reducing

variation and eliminating non-value added activities, that ultimately result in increased financial

performance and customer satisfaction. Like any improvement initiative, Lean Six Sigma can fail

for a variety of reasons including lack of management support, poor project selection, and the

challenge of working with suppliers to establish just in time supply chains.

Hoerl (1998), in researching key reasons why Six Sigma is successful, states that

continued support of top management and enthusiasm are critical to achieving positive results.

Hoerl describes how the promotion process at General Electric now includes a requirement for

training in Six Sigma and completion of several projects. Sandholm and Sorqvist (2002) state

that lack of management commitment and visible support is the number one reason why Six

Sigma fails. General Electric and Motorola have emphasized the role of top management in their

successful Six Sigma initiatives. Sandholm and Sorqvist note that they are beginning to see a

trend in some companies where Six Sigma is not run by top management, creating a lack of

ownership in the process. Another problem Sandholm and Sorqvist describe is the role of middle

management. The authors suggest that getting middle managers involved in the process is a

challenge many companies are facing, and without the support of middle management, who are

most often responsible for key functional areas within a company where projects take place, Six

Sigma is less likely to succeed.

Six Sigma is defined by projects. The challenge lies in picking the right projects.

Sandholm and Sorqvist (2002) suggest that the prioritization and selection of projects is critical

to the success of a Six Sigma program. Sandholm and Sorqvist state that several key factors to


selecting projects must be considered. They include financial return, customer impact, and

productivity improvements. Gijo and Rao (2005) argue that project selection must align with an

organization’s goals and objectives. Through their research Gijo and Rao have uncovered many

projects where team members lacked the authority to implement the project or collect valid data,

causing projects to fail. Gijo and Rao also state that companies often place stringent expectations

on belts causing them to consider everything a project when in fact it is simply a task. Gijo and

Rao also write that project scope creep also creates a problem that can grow into an

uncontrollable project that cannot be completed in the expected timeframe.

Lean, despite being significantly less complex than Six Sigma also presents several

similar challenges. Upadyne et al. (2010) argues that commitment from top management and

total employee involvement is necessary to create a truly lean organization. A second challenge

in implementing Lean is working with suppliers to establish just in time deliveries of materials.

Upadyne et al. suggest that significant up front work is necessary to establish the development of

efficient supply chains, creating what can be significant investment requirements to implement a

lean supply chain.

Even though there are challenges to implementing Lean Six Sigma the research suggests

the benefits typically outweigh the disadvantages. Lean has been argued to improve delivery

times, reduce defects, increase on-time delivery, increase productivity, and provide an increased

return on assets (Lee & Oakes, 1996; Sohal, 1996). Six Sigma has also been widely shown to

lead to bottom line savings (Eckes, 2001; Hoerl, 1998).

The Future of Lean Six Sigma

What is the future of Lean Six Sigma? George (2002) argues organizational resources

will become scarcer, creating the need to continue to combine Lean and Six Sigma expertise.


Edgeman (2000) believes that the focus on bottom line savings and fewer world resources will

continue to push organizations to further scrutinize projects that result in significant return on

investment, creating more demand for Lean Six Sigma initiatives.

Edgeman and Bigio (2004) suggest that an increasing level of accountability for the

public sector will help establish an increase in the popularity of Lean Six Sigma due to the

methodology’s documented ability to produce results. Another sector suggested by Edgeman and

Bigio that is ripe for the need of Lean Six Sigma is the health care industry. As health care costs

continue to rise, insurance companies and government agencies will also likely tap into the

potential of Lean Six Sigma. As long as Lean Six Sigma continues to produce results it will

arguably continue to find new uses and spread across multiple industries leading to what will

likely evolve into the next quality management methodology.

Conclusion

The evolution of quality management over the last century has changed the way people

around the world live. Starting with Taylor and his concept of scientific management, Ford in the

development of the production line, Shewhart and Deming bringing the concept of variation

reduction to management, and Ohno spending decades at Toyota perfecting the process of

eliminating waste, they have all influenced the philosophy and methods forming the foundation

for Lean Six Sigma. The culmination of this work has contributed to the standard of living and

working conditions for the majority of the world, which have arguably increased exponentially in

the span of a relatively short time. What will come next is yet to be determined, but what is

almost certain is the process of quality improvement will continue moving forward, and evolve

into something that is sure to prove even more beneficial to society.


References

Addey, J. (2004). The modern quality manager. Total Quality Management, 15(6), 879-889.

Beer, M. (2003). Why total quality management programs do not persist: The role of

management quality and implications for leading a TQM transformation. Decision

Sciences, 34, 623-642.

Bertels, T. (2003). Rath & Strong’s six sigma leadership handbook. New York: John Wiley &

Sons.

Brewer, P. C., & Eighme, J. E. (2005). Using six sigma to improve the finance function.

Strategic Finance, 86, 26-34.

Chen, I. J., Coccari, R. L., Paetsch, K. A., & Paulraj, A. (2000). Quality managers and the

successful management of quality: An insight. Quality Management Journal, 7(2), 40-54.

Cheng, T. C. E., & Podolsky, S. (1996). Just in time manufacturing: An introduction (2nd ed.).

London: Chapman & Hall.

Deming, W. E. (2000). Out of the crisis. Cambridge, MA: MIT Press.

Eckes, G. (2001). The six sigma revolution: How General Electric and others turned process

into profits. New York: John Wiley & Sons.

Edgeman, R. (2000). BEST business excellence: An expanded view. Measuring Business

Excellence, 4(4), 15-17.

Edgeman, R., & Bigio, D. I. (2004). Six sigma as a metaphor: Heresy or holy writ? Quality

Progress, 37(1), 25-30.

Evans, J. R., & Lindsay, W. M. (2005). The management and control of quality (6th ed.). Mason,

Ohio: South Western College Publishers.

Ford, H. (1922). My life and work. New York: Doubleday, Page, & Company.


Fuchsberg, G. (1992, October 1). Total quality is termed only a partial success. The Wall Street

Journal, pp. B1.

George, M. L. (2002). Lean six sigma. New York: McGraw-Hill.

George, M., Rowlands, D., & Kastle, B. (2004). What is six sigma? New York: McGraw-Hill.

Gijo, E. V. & Rao, T. S. (2005). Six Sigma implementation-Hurdles and more hurdles. Total

Quality Management, 16(6), 721-725.

Gopal, K., Kristensen, K., & Dahlgaard, J. (1995). Quality motivation. Total Quality

Management, 6, 427-434.

Hahn, G. I., Hill, W. J., Hoerl, R. W., & Zinkgraf, S. A. (1999). The impact of Six Sigma

improvement-A glimpse into the future of statistics. The American Statistician, 53(3),

208-215.

Harry, M. (2000). Six Sigma. New York: Currency.

Harry, M., & Schroeder, R. (2000). Six Sigma: The breakthrough management strategy

revolutionizing the world’s top corporations. New York: Currency.

Hirano, H. (1995). 5 pillars of the visual workplace: The sourcebook for 5S implementation.

New York: Productivity Press.

Hoerl, R. W. (1998). Six Sigma and the future of the quality profession. IEEE Engineering

Manager Review, 26(3), 87-94.

Jadhav, S. D., & Khire, M. Y. (2007). Lean manufacturing: An exemplar in manufacturing.

Manufacturing Technology & Research, 3(3/4), 59-62.

Jing, G. G. (2009). A lean six sigma breakthrough. Quality Progress, 42(5), 24-31.

Lee, G. L., & Oakes, I. K. (1996). Templates for change with supply chain rationalization.

International Journal of Operations and Production Management, 16(2), 197-209.


Liker, J. K. (2004). The Toyota way: 14 management principles from the world’s greatest

manufacturer. New York: McGraw-Hill.

McLachlin, R. (1997). Management initiatives and just in time manufacturing. Journal of

Operations Management, 15(4), 271-292.

Mader, D. P. (2008). Lean six sigma’s evolution. Quality Progress, 41(1), 40-48.

Nakajima, S. (1988). Introduction to TPM: Total productive maintenance. New York:

Productivity Press.

Naumann, E., & Hoisington, S. H. (2001). Customer centered six sigma: Linking customers,

process improvement, and financial results. Milwaukee, WI: American Society for

Quality.

Neave, H. R. (1990). The Deming dimension. Knoxville, TN: SPC Press.

Ohno, T. (1988). Toyota production system: Beyond large-scale production. New York:

Productivity Press.

Okes, D., & Westcott, R. T. (2001). The certified quality manager handbook (2nd ed.).

Milwaukee, WI: ASQ Quality Press.

Pande, P., Neuman, R., & Cavanagh, R. (2000). The Six Sigma way: How GE, Motorola, and

other top companies are honing their performance. New York: McGraw-Hill.

Powell, T. C. (1995). Total quality management as competitive advantage: A review and

empirical study. Strategic Management Journal, 16, 15-38.

Pyzdek, T. (2003). The six sigma handbook, revised and expanded: The complete guide for

greenbelts, blackbelts, and managers at all levels. New York: McGraw-Hill.

Sandholm, L. & Sorqvist, L. (2002). 12 requirements for Six Sigma success. Six Sigma Forum

Magazine, 2(1), 17-22.


Schroeder, R. G., Linderman, K., Liedtke, C., & Choo, A. (2008). Six sigma: Definition and

theory. Journal of Operations Management, 26, 536-554.

Sekine, K. (1992). One-piece flow: Cell design for transforming the production process. New

York: Productivity Press.

Shah, R., & Ward, P. T. (2003). Lean manufacturing: Context, practice bundles, and

performance. Journal of Operations Management, 21(2), 129-149.

Shah, R., Chandrasekaran, A., & Linderman, K. (2008). In pursuit of implementation patterns:

The contenxt of lean and six sigma. International Journal of Production Research,

46(23), 6679-6699.

Shewhart, W. A. (1980). Economic control of quality and manufactured product. Milwaukee,

WI: American Society for Quality Control.

Shingo, S. (1989). A study of the Toyota production system. New York: Productivity Press.

Snee, R. D., & Hoerl, R. W. (2003). Leading Six Sigma. New York: Prentice-Hall.

Snee, R. D., & Hoerl, R. W. (2007). Integrating Lean and Six Sigma: A holistic approach. Six

Sigma Forum Magazine, 6(3), 15-21.

Sohal, A. S. (1996). Developing a lean production organization: An Australian case study.

International Journal of Operations & Production Management, 16(2), 91-102.

Taylor, F. W. (1916, December). The principles of scientific management: Bulletin of the Taylor

Society. An abstract of an address given by the late Dr. Taylor before the Cleveland

Advertising Club, March 3, 1915.

Upadhye, N., Deshmukh, S. G., & Garg, S. (2010). Lean manufacturing for sustainable

development. Global Business and Management Research: An International Journal,

2(1), 125-137.


Wheeler, D. J., & Chambers, D. S. (1992). Understanding statistical process control (2nd ed.).

Knoxville, TN: SPC Press.

Williams, K., Haslam, C., & Williams, J. (1992). Ford versus “Fordism”: The beginning of mass

production? Work, Employment & Society, 6(4), 517-555.

Womack, J. P., Jones, D. T., & Roos, D. (1990). The machine that changed the world. New

York: HarperCollins Publishers.

Womack, J. P., & Jones, D. T. (1996). Lean thinking: Banish waste and create wealth in your

corporation. New York: Simon & Schuster.


Appendix A

Lean Six Sigma Historical Timeline 1890s Frederick Taylor introduces scientific management.

1902 Sakichi Toyoda creates a device to detect broken threads in a loom (Poka-Yoke).

1908 Henry Ford introduces the automobile with interchangeable parts.

1913 Henry Ford creates the production line at the Highland Park plant.

1926 Henry Ford introduces the term “mass production”.

1930s The concept of takt time (building to the rate of customer demand) is introduced in the

German aircraft industry and Mitsubishi brings the idea from Germany to Japan.

Shewhart introduces statistical quality control and the plan, do check, act cycle.

1937 Kiichiro Toyoda establishes the Toyota Motor Company and just in time (JIT)

production.

1941 The U.S. War Department introduces training within industry (TWI) to U.S. industry that

includes job instructions, methods, and training, which spreads to Japan after the war.

1950s Taiichi Ohno introduces Kanban cards and the concept of supermarkets for use with JIT.

Deming introduces his 14 points and seven deadly sins and diseases.

1980s Total quality management (TQM) is introduced to industry.

1990s Motorola introduces Six Sigma

Womack, Jones, and Roos write The Machine that Changed the World, introducing the

term Lean.

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