It was one of those minor design changes that you really wouldnâ€™t expect to move mountains. Pedro Sostre and his team at the design firm Sostre & Associates simply added an extra link to the horizontal navigation of a clientsâ€™ website. But the move killed performance about 30 percent. What happened?
Web analytics provided the answer. Sostre looked at heat maps showing visualizations of usersâ€™ clicks on the homepage. He discovered that users had all but stopped using the search function, which had been pushed farther over by the new navigation item. â€œThe fact that the search bar moved over 150 pixels caused the usage of it to drop by 80 percent,â€ Sostre says.
If you’re even slightly interested in web design for usability you should read the whole thing.