Interaction Design

“The intractability of the software construction process – particularly the high cost of programming and

the low quality of interaction – is simply not a technical problem”

Alan Cooper

software

• Why is most software bad? Frustrating to use, buggy.

• Not programmers fault – they are often the agents of bad software but not the cause

• They are not given sufficient time, clear enough direction or adequate designs to succeed

• Providing these should be the job of the Executive and Product teams

• But they aren’t delivering – why?

• Not (just) stupidity

• They don’t have the right tools

software

• Businesses are structured & measured by a system born in mercantilism and refined in industry

• It measures the wrong thing in the information age

old methods

old methods

• In the industrial age products were manufactured from solid materials

• The money it took to create them were dominated by variable costs

• Costs that varied with the amount of stuff made.

old methods

• Software production is not like this

• It does not consume raw materials – no manufacturing costs

• The variable costs that dominated manufacturing are non-existent in software production

• Software production is not a fixed cost or a variable cost – and it is not R & D...

square peg, round hole

• ...but in practice it is treated like a manufacturing process (a variable cost)

• Businesses grow profits by increasing revenue or decreasing costs

• Decreasing costs was quickest and easiest in the manufacturing age

square peg, round hole

• But software production does not behave like a variable cost – trying to ‘reduce’ it doesn’t work

• Worse, it cuts off the only other course of action – increasing revenue by increasing quality means increasing production effort.

• Interaction design is the tool used to intelligently increase production effort

• Make sure all production effort contributes to quality and revenue

misdirected effort• IxD is the bridge between engineering and business

• Without adequate communication they tend to talk past each other

Feat

ures

Engineers choose features Sales & marketing choose features Utilised featuresexpert beginner

• How do we ensure that effort has real impact on the customer?

principlesGood software promotes “flow”

A psychological state in which people can concentrate fully with out peripheral distraction

• Reflects user’s mental model

• It does not converse

• Keeps tools close at hand

• Provides modeless feedback

How do we design such software?

orchestrationGood software should be invisible

• Orchestration is the process of ensuring all elements work harmoniously

• Less is more

• Don’t design for corner cases

• Reflect status – but don’t report normalcy

• Don’t interrogate

navigationNavigation is a chore even if it is in-line with the user’s flow

• Keep the number of pages to a minimum – preferably one.

• Keep the number of panes within a page to a minimum – no more than three.

• Provide sign-posts: fixed persistent elements.

• Provide overviews: thumbnails, bread-crumbs

exercise

• Don’t force the user to go to a different page – especially to do something that effects his current one

• Don’t force the user to remember things

• Try to allow input where you have output

Exercise is interaction that does not contribute to a user’s goal – eliminate it.

inflection

• Organise layout according to three attributes

• Frequency of use

• Degree of dislocation

• Degree of risk

Organise the interface to minimise the most common navigation path

visuals

• Masaaki Kurosu & Kaori Kashimuru

• ATM study

• Replicated by Noam Tractinsky

• Usability and aesthetics strongly correlate

• Emotion and cognition are interlinked – Norman ’04

• Happy people are more effective in finding alternate solutions & are therefore tolerant of minor difficulties – Alice Isen

Beautiful things work better!

conclusion

No more management by dead-line.

Know what you are building, who for, and know when you are finished

questions