September 09, 2002

The trouble with usability guidelines
Jared Spool has a new article that questions the value of guidelines called "Evolution Trumps Usability Guidelines."

Jared is controversial (as ever), but as usual there is some truth to what he's saying. I'm not willing to chuck all guidelines out the window, but I'll add my opinions to what Jared has already stated. Let me state up front that I maintain and promote use of a set of guidelines in my day to day work, so I have some experience with guidelines. I've also used guidelines and "style guides" as coaches at times when looking for advice on how to tackle certain design issues.

Problems with guidelines:

  1. Many guidelines aren't based on research. The National Cancer Institute's Research-Based Web Design & Usability Guidelines are an attempt to bring more credibility to guidelines.
  2. Compliance with guidelines can be hard to measure if they are vague or poorly written
    E.g., "Ensure descriptive terms or pictures are used: Use clear and informative labels to describe products on-line" (from Serco's Ecommerce Guidelines)
  3. Many guidelines don't really provide much value
    E.g., "Every Web page should contain at least one link." (from the Yale Web Style Guide) How many people read this guideline and said "Duh!"? Do you think it matters what that one link is?
  4. Guidelines can get outdated.
    E.g., Sun's Writing for the Web Style Guide was authored by Jakob Nielsen who hasn't been at Sun for a number of years. The style guide doesn't look like it's been updated since at least 1998.
  5. Guidelines by definition generalize about design - without regard to differences in audiences, tasks, work environments or other specifics that should play a major factor in designing usable applications. Guidelines make lots of assumptions and don't necessarily tell you what assumptions were made.
    E.g., "International users: Remember that you are designing for the World Wide Web. Your readers could be the people down the street, or people in Australia or Poland." (from the Yale Web Style Guide) clearly not considering intranets, extranets, or other web applications where you may really know the limits of your audience's reach.
  6. Guidelines aren't a recipe for success -- even if you can comply with every guideline, your application might not be very usable. They aren't a replacement for a good User-Centered Design (UCD) process.
  7. Guidelines are not comprehensive -- they don't cover all or even most design scenarios.
  8. Different sets of guidelines may contradict each other.
    E.g., Spool and Nielsen regulary go toe-to-toe on the topic of web search.
  9. Guidelines can be hard to use. A good set of web guidelines generally is pretty large and can't be easily absorbed by designers -- especially novice designers.
    E.g. Nielsen Norman Group has published 592 different web usability guidelines in five separate reports.
  10. It seems some people think guidelines are a replacement for the methods in UCD and try to short-cut the design process by using them instead of usability testing, prototyping, etc. This makes guidelines dangerous -- people who don't know how or when to use them will mis-use them. By following guidelines blindly, you can shoot your design in the foot. (Yes, of course designs have feet - how else do you explain "walk-throughs?")

There are also some things that are good about guidelines -- but I'll cover that topic in another post.

Let me know what you think -- email: Lyle_Kantrovich at Bigfoot dot com

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