1. Unclear Statement of Purpose - Many companies, particularly in the high tech industry, use vague or generic language to describe their purpose. Obscuring this basic fact makes it much harder for users to interpret a website's information and services.

2. New URLs for Archived Content - Archives add substantial value to a site with very little extra effort. Although more and more sites are archiving old content, most sites still fail to maintain good archives. Some sites treat archives as a separate site area, assigning pages new URLs when they move them from the main area into the archive.

3. Undated Content - Without dates on articles, press releases, and other content, users have no idea whether the information is current or obsolete. It's great to keep content in archives. The Alertbox, for example, gets 80% of its readership for old columns, which readers continue to find useful. But some facts and recommendations are strongly date-dependent, such as when I recommend using a certain version of a software package for another two years. Obviously, I mean two years from the day the article was written; if readers can't see the date, they won't know how to follow the recommendation.

4. Small Thumbnail Images of Big, Detailed Photos - It's great that websites are now using smaller pictures. Avoiding the bloated designs of the past decreases download time and increases information richness. It's also good when sites link small pictures to bigger pictures, so users have the option of seeing the image in more detail.

5. Overly detailed ALT Text - Many sites have begun paying attention to users with disabilities and are following accessibility guidelines, such as including ALT texts for images.
Unfortunately, some sites don't realize that ALT text is a user interface element, not a statement of political correctness. ALT text should help blind users (and others who can't see images) navigate and operate the site. The text should describe the image's meaning for the interaction and what users need to know about the image to use the site most effectively. There is no need to describe irrelevant visual details.

6. No "What-If" Support - Comparing and choosing between alternatives is the basis for most critical Web tasks, yet most websites don't support users who want to consider alternatives. Some websites do let users pick out a few products and view a comparison table, but such tables typically have low usability and don't highlight the most important differences between products.

7. Long Lists that Can't Be Winnowed by Attributes - It used to be that Web sites offered one or two things. Now it's common to find sites with thousands or millions of items. Wonderful, but that means that item listings are often very long and hard to use.

8. Products Sorted Only by Brand - Sites that offer many items ought to provide winnowing and sorting, which is a highly useful way to deal with lists and is fortunately fairly common. Unfortunately, many sites only let users sort items by brand.

9. Overly Restrictive Form Entry - Put the burden on the computer, not the human: let users enter data in the format they prefer. A typical example is when forms ask users for their first and last names as two items, rather than simply letting users enter their full name in a single field, which is much faster to type. Many sites, for example, force users to enter credit card numbers as 1234567890123456, rather than letting them put spaces between groups of four digits, which significantly reduces the risk of errors.

10. Pages That Link to Themselves - This point was discussed in detail as item #10 on my list of ten most violated homepage guidelines, but it's important for all pages, not just homepages.

Web Usability: Two Steps Forward, One Step Back - Many of this year's top design mistakes actually indicate a happy phenomenon: we are making progress in Web usability. Now that sites are doing certain things correctly, we get hit by second-order phenomena that only cause problems because users have progressed past the first-order issues.