I noticed that Apple lost track of usability since Cook came after their release of a new keyboard at first, new arrows buttons on it are completely unusable, on older keyboards they had spacing between the left/right and buttons on top, now they extended left/right buttons and it makes it incredibly hard to "feel" where they are, and the fact that MacBooks pros still have an old layout makes it a night mare to switch between desktop and laptop programming.

Another one is a new lock screen on iOS 10, sometimes the fingerprint does not work or the finger is dirty and i know I want to unlock it with a pin, before I used to be able to just swipe right away and type the pin, now it won't let me and I have to repeatatly press the home button until it figures out that the fingerprint won't work and it has to show me the pin enter screen.

Might be little things but it's what used to separate Apple from the crowd, I don't want them to lose focus on those. And don't get me started on the new OS X, which makes my maxed out 2014 rMBP look like slow PC from 2000.