1. Bad Search
Overly literal search engines reduce usability in that they’re unable to handle typs, plurals, hyphens, and other variants of the query terms.A related problem is when search engines prioritize results purely on the basis of how many query terms they contain, rather than on each document’s importance.
2. PDF Files for Online Reading
Users hate coming across a PDF file while browsing, because it breaks their flow and reduce its speed. Even simple things like printing or saving documents are difficult because standard browser commands don’t work. Layouts are often optimized for a sheet of paper, which rarely matches the size of the user’s browser window. Bye-bye smooth scrolling. Hello tiny fonts.
Worst of all, PDF is an undifferentiated blob of content that’s hard to navigate.
3. Not Changing Color of Visited Links
A good grasp of past navigation helps you understand your current location in the wesbsite, since it’s the culmination of your journey. Knowing your past and present locations in turn makes it easier to decide where to go next. Links are a key factor in this navigation process. Users can exclude links that proved fruitless in their earlier visits. Conversely, they might revisit links they found helpful in the past.
Most important, knowing which pages they’ve already visited frees users from unintentionally revisiting the same pages over and over again.
4. Fixed Font Size
CSS style sheets unfortunately give websites the power to disable a Web browser’s “change font size” button and specify a fixed font size. About 95% of the time, this fixed size is tiny, reducing readability significantly for most people over the age of 30-40.
5. Page Titles With Low Search Engine Visibility
Search is the most important way users discover websites. Search is also one of the most important ways users find their way around individual websites. The humble page title is your main tool to attract new visitors from search listings and to help your existing users to locate the specific pages that they need.
The page title is contained within the HTML <title> tag and is almost always used as the clickable headline for listings on search engine result pages (SERP). Search engines typically show the first 66 characters.
6. Opening New Browser Windows
Opening up new browser windows is like a vacuum cleaner sales person who starts a visit by emptying an ash tray on the customer’s carpet. Don’t pollute my screen with any more windows, thanks (particularly since current operating systems have miserable window management).
Designers open new browser windows on the theory that it keeps users on their site. But even disregarding the user-hostile message implied in taking over the user’s machine, the strategy is self-defeating since it disables the Back button which is the normal way users return to previous sites.