Helping clients become self-sufficient in usability is one of the prime motivations of our work. Our usability consulting experience showed us many clients who made the same mistakes when trying to make usability happen and so failed to reap the business benefits. We also noticed other clients who got it right and went from strength to strength.
“Continually delighted with their expertise and pragmatic solutions, we engage Userfocus in most of our key strategic initiatives. We work with only a few select external partners, and Userfocus is at the top of our short list.”
– Ali Vassigh, Whirlpool Corporation.
Clients who got it wrong tended to see usability as screen design: choosing the correct fonts, colours and icons. In fact, usability is a process: it is not something that can be stapled on at the end of development. To say that usability is about screen design is as erroneous as saying that branding is all about a good logo. Of course screen design plays a role in usability, but it is a small role. This means that optimising the colours, fonts and icons on your site will improve usability by, at best, 15%. It’s like the old adage: you can put make-up on a pig, but it’s still a pig.
Clients who got it right realised that screen design is just one of three important components.
Web sites that score high on usability also show a second key feature: consistency.
Consistency accounts for about 25% of a web site's usability. We can all point to annoying inconsistencies in (or between) much of the software we use. For example, the “Cut and Paste” operation in Microsoft Excel works differently from every other piece of software — even other Microsoft products. Choose “Cut” in Microsoft Word and the selection disappears. Choose “Cut” in Microsoft Excel and ‘marching ants’ appear around the selection, but it remains where it is.
The third component of usability, the remaining 60%, is accounted for by task focus.
You know a web site has task focus when you get a warm feeling that the person who designed the site knew exactly what you wanted to do. The site works the way you expect. There is no need to go searching through menus or dialogue boxes for obscure commands: the main things you want to do are there, in front of you: easy to find and simple to carry out. The web site delights you. Another example comes from the world of successful computer games: very quickly, the “interface” disappears and you are exploring the world of the game — the task.
Rules for good visual design are plentiful — you can get them from a book. Using code libraries and then testing against a Style Guide can achieve consistency. But achieving task focus is much more complicated — it requires a process, and it is the substance of the usability process standard that we use.
One of the strengths of the method is that it can be tailored to support existing design methodologies. Because the process is not tied to any one notation or tool set, it can be easily adapted to create models in whichever notation and tool set the programming team uses. By following our human-centred design process, project managers, designers and developers can ensure that systems will be effective, efficient and satisfying for customers.
The method has four main lifecycle phases (shown in the figure):
Enlarge image (opens in in a pop-up window).
Based on the International Standard, ISO 13407:1999 "Human-centred design processes for interactive systems", our method has been applied to a range of clients in diverse industries.
The ISO standard describes four principles of human-centred design:
...And four key human-centred design activities
The standard itself is generic and can be applied to any system or product. We have applied it in organisations using formal PRINCE2 methodologies and in small, fast-moving software development companies.
The approach is iterative and deliverable-based; forms or designs are completed at the end of each stage, which then constitutes the requirements and design specification for a project.