Adaptive Menus were not successful. In my opinion, they actually add complexity to the interface. Why? Several reasons:
- There was no way to get the default "short" menu right. Although conventional wisdom holds that "everyone only uses the same few features in Office," the reality is that people use an amazingly wide range of functionality. So, one person's ideal default "short" menu was exactly the wrong thing for someone else.
- Once the default short menu was wrong, the user was forced to scan the menu. However, scanning adaptive menus requires two passes: scan the short menu, press the chevron, then back to the top to scan the long menu. Because the secondary menu items could appear between short menu items, the appearance of the long menu caused your scan to reset. As a result, scanning menus took twice as long Even if they had designed it so that pushing the chevron revealed the bottom part of the menu (and the top part didn't change), at least you'd only have to scan the menu once. So, adaptive menus added a lot of inefficiency.
- Auto-customization, unless it does a perfect job, is usually worse than no customization at all. Although the algorithm used to promote and demote menu items is rather complex and well thought-out, it's not perfect. Because it's not perfect, it does the wrong thing a lot of the time. (If it's even clear what a "right thing" is for a feature like this.) What people experienced is a sense randomness and unpredictability: one time, a menu item would be in a certain place, and then two days later it wasn't there anymore.
As a result, even for the Office 2007applications that are still using old-style UI (such as Publisher, Project, and Visio), we've turned off Adaptive Menus by default.