from Jakob Nielsen
Summary: There are ten usability mistakes that about two-thirds of corporate websites make. The prevalence of these errors alone warrants attention, especially since they appear on sites with significant investment in usable design.I typically focus my top-ten lists on issues that I think are the most important and most in need of attention. This time, I've used a different criterion: I've focused on the known usability principles that designers most frequently violate. Whether big or small, the very prevalence of these usability problems makes them worthy of attention.The frequency statistics are based on the numerous homepage reviews that my company has performed since I published my book on homepage usability. This data source introduces a bias, because only big companies or government agencies with a substantial usability commitment will invest $10,000 to have an independent expert assess its homepage design. However, we can turn that bug into a feature: if companies with a demonstrated commitment to usability make certain mistakes, they must be particularly slippery pitfalls.
For each of the ten most frequent mistakes, I state the deplorably low percentage of homepages that follow the guideline. I've sorted the list by compliance rate: number one is the guideline that the fewest sites follow (that is, the mistake that's made most often).
