These are not original mistakes, in fact most of them have been violated ever since I started caring about usability. Nonetheless, these are the most glaring ones of 2008.
- Styled push buttons
Most common examples: Admin interfaces (WordPress, Habari), personal websites, high-profile expensive looking websites. Most common excuses: “The default push button doesn’t fit the design”, “We’re trying to create a uniform look across platforms”, “Design matters”.
- Other than white background in searchboxes and inputfields
Most common examples: Personal weblogs.
- “Click here” links
Most common examples: High traffic weblogs (Joystiq, Lifehacker).
- Bad link designs
Most common examples: Small weblogs. Most common excuses: “This is a minimalist design”.
- Inability to distinguish links from visited links
Most common examples: All types of websites. Most common excuses: “Oh right, I forgot that”.
- Links open in new browser windows.
Most common examples: Extremely high traffic websites (Digg).—Sidenote: These guys forget Jakobs Law of the Web User Experience: “Users spend most of their time on other websites”.
- Full Flash websites
Most common examples: Movie websites, photographers websites. Most common excuses: “We’re special!”.
- Dropdown navigation
Most common examples: Content-heavy websites (Adobe).
- Windows that change size
Most common examples: Popup image slideshows on news websites.
- Content that requires registration
Most common examples: Digital newspapers (NYTimes). Most common excuses: “Our content is so good, it’s worth requiring registration”.