If you think in terms of click areas only, the launcher is a series of hot boxes you can click on. By having the launcher re-fold constantly, those boxes always return to the same position, which allows for users to have a higher degree of confidence about what they are about to mouse into, even with a hidden launcher.
I agree that predictability is important, but I think the current implementation prioritizes *overall* predictability (a.k.a. launcher *always* returns to *the same fixed position*), when it should be prioritizing *recent* predictability (a.k.a. launcher stays as much as possible in the position it was the *last time the mouse was over it*), which top folding would allow.
Further if you are looking for something at the bottom of the launcher, having the mouse enter the launcher at any position will cause it to unfold at that position as well (so the item it enters over stays under the mouse).
And because of that, an extra movement of the mouse is required if you miss the target, something that gets more and more likely to happen as the number of icons increase, and can get quite annoying if the use is frequently clicking on icons at the bottom. And since bottom means recently opened in the Unity launcher, the bottom part tends to concentrate the windows involved in the current workflow, so this situation does not seem rare. -- Mailing list: https://launchpad.net/~unity-design Post to : unity-design@lists.launchpad.net Unsubscribe : https://launchpad.net/~unity-design More help : https://help.launchpad.net/ListHelp
