Usability of a potential design

Three-quarters of the way through a Five Sketches™ session, to help iterate and reduce the number of possible design solutions, the team turns to analysis. This includes a usability analysis.


After Œ informing and defining the problem  without judgement  and  generating and sketching lots of ideas  without judgment , it’s often a relief for the team to start Ž  analysing and judging  the potential solutions by taking into account the project’s business goals, development goals, and usability goals).

But what are the usability goals? How can a team quickly assess whether potential designs meet those usability goals? One easy answer is to provide the team with an project-appropriate checklist.

Make your own checklist. You can make your own or find one on the Internet. To make your own, start with a textbook that you’ve found helpful and inspiring. For me, that’s About Face by Alan Cooper. To this, I add things that my experience tells me will help the team—my “favourites” or my pet peeves. In this last category I might consult the Ribbon section of the Vista UX Guide, the User Interface section of the  iPhone human-interface guidelines, and so on.

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What “standard” GUI means

If you decide to forego the design stage and reuse or copy an existing GUI or interaction design, your life is easier.

But how do you know when you have a standard to follow?

An obvious place to find standards is in the precedents set by your own Development team. If your standards are not documented, consider a BarnRaising afternoon, once a month, until the high priority standards are documented.

And while many of us have enjoyed the comfort of a style guide to follow, there’s more flexibility now, as Milan Guenther wrote in Photos for interaction:

© Boxes and ArrowsThe barrier between web pages and desktop software is beginning to disappear, and modern rich client user interface technologies such as Silverlight/WPF, Air, or Java FX enables designers to take the control over the whole user experience of a software product. Style guides for operating systems like MacOS or Windows become less important because software products are available on multiple platforms, incorporating the same custom design independently from OS-specific style guides. Software companies and other parties involved begin to use the power of a distinct visual design to express both their brand identity and custom interactive design solutions to the users.

But not everything needs to be reinvented. There are plenty of common user tasks that the operating system supports with default GUI, including Open, Save, Print, Search/Replace, Font, Color, and Page Setup tasks. These also defaults serve as patterns for the custom GUI that you design—the visible objects, and the invisible ones, such as:

  • mental models
  • workflows

The two traditional operating systems give us plenty of standard controls to meet any design challenge, including buttons, boxes, sliders, progress indicators, notifications, and much more. If you develop for MacOS, Apple publishes various guidelines, including for user experience. If you develop for Windows, the Vista UX Guide is updated regularly, with new sections for ribbons, touch, pen, and printing.


Despite everything I just said about following standards, I’m also a big believer in changing things that are broken. An example: on my desk I can have two sheets of paper, copies of the same document. On my desk, they don’t need to have different names—even if each sheet has different comments written on it by different people. On my computer, the same two documents must either have different names or be in different folders. Surely the computer can keep track of both, uniquely, without forcing the user to choose different names? The unique-name requirement is an example of architecture dictating the interface. Alan Cooper wrote about this and other examples of tail wagging the dog in About Face: The essentials of user-interface design.

If you’re wondering when to copy/reuse, and when to design, check out my blog post, GUI: copy it or design it?