An Introduction to Theory of Constraints (TOC)Laz Allen, Agile Coach at Skyscanner

Introductions

Laz Allen

https://www.linkedin.com/in/lazallen

@LazAllen

Agile Coach at Skyscanner

Overview

Overview

• What is the Theory of Constraints (TOC)?• A TOC tool you may not have heard about• A TOC refresher that you might have

What is TOC?

2 Words to describe TOC

FOCUS & LEVERAGE

Eli Goldratt 1947-2011

For continuous improvement

Theory of Constraints

1. Optimise the whole system, not individual parts

2. Optimise for throughput of value before work in progress and cost

3. There will be ONE (or few) constraint, cause, tension causing most of the problems

Slide credit: It's systems all the way down! By Chris McDermott, Agile Coach

Thinking Processes vs Solutions

Solving Dilemmas with TOC

Evaporating Clouds

Evaporating Clouds

ObjectiveA

Need C

Need B

Want D’

Want D

CONFLICT

Flow Systems and the 5 Focusing Steps

Spot the constraint

Flow Analysis (Kanban)• Quick and Simple,

Compatible with

Scrum etc… !

Just stage by stage

Example of a flow system in Skyscanner

Partner Management System

Commercial / Account Managers

Triage(Partner Success

Managers)

Integration Development (Partner Eng)

The 5 Focusing Steps

Escalator Example

Holborn London Underground Station

Value Stream MappingFinding waste within the constraint

Pre-Validated Techniques

Small Batch Sizes

20 days

5 days

Lead time = waiting time + build time

Gloria Mark of the University of California

found that a typical office worker gets only 11 minutes between each interruption,

while it takes an average of 25 minutes to return to the original task after an interruption.

Pre Validated Techniques• Buffer in front of

constraint• teams able to deliver

value independently • Build Quality In• Prioritising

Still work for one stage or many