The term ‘usability’ refers to how well someone might use a human-made tool to achieve a particular goal. Within the context of web design it refers to how efficiently a task can be completed, be it purchasing an item, looking for information or completing a function. The usability of a device is best summarised by Jakob Nielson's and Ben Shneiderman's five defining factors:

• Learnability (e.g. intuitive navigation)
  
• Efficiency of use
  
• Memorability
  
• Few and non-catastrophic errors
  
• Subjective satisfaction

These five factors should be at the front of mind during any web design project. Furthermore, the process should be user-centred so that its outcome is more likely to rate well against each of these factors upon completion. However, what becomes problematic is the measurement of ‘Subjective satisfaction’. Although this is the most difficult factor to measure, herein lies the greatest opportunity to create a truly unique and memorable experience.

Usability rules have become ubiquitous and it is almost easy to forget to even question them. We refer to previous work or best practice examples which all suggest the same things which in turn validate our decision to prescribe the same thing over and over again. All outcomes are categorically 'usable' but at the same time risk being indistinguishable. For the same reason I would hate Volvo to be the only car on the road I would also hate to see every Web site look the same. Essentially what I am interested in is the less discussed (and equally important) idea of knowing when to break convention and when to invite innovation into the process of creating a usable product.

At this point I could refer to many, many products which in my mind have exceeded all five of Nielson and Schniederman’s five factors whilst also breaking convention and ultimately providing an elegant outcome which is truly innovative. The iPod is an obvious choice. The very nature of how the device is used by its owner makes it unique and desirable. Instead of compromising the design, in effect a focus on usability has completely informed the design. This allows the product to ‘cut-through’ and establish itself as a one-of-a-kind.

Another example is Droog’s toilet door handle for the blind. This simple door handle appears much like any other. When you clasp the door handle you instantly feel the braille bumps behind the handle which:

• for the blind, instantly identifies the ‘male toilet’ from the ‘female toilet’ (without having to search for any additional reference)
• for the non-blind, instantly raises social awareness of the blind
• and as a piece of design is uncompromising

Given today is World Usability Day, I think it is important that we consider how to use usability as an aid in developing great refreshing design rather than a catalyst for more of the same. Yes usability is important (if not critical) so let’s make sure we truly understand it, embrace it and help it improve people’s day to day lives.

Tim Kotsiakos, Creative Director

Labels: Design and Usability