It's no news that USB mass storage support got stripped from Android (I'm not quite sure ... either in 3.* or in 4.* versions). This change introduced a number of advantages over the old way, but at the same time a quite serious and longstanding bug surfaced with it: sometimes (or whenever ...) you change something in the filesystem on your phone, the change will not be reflected on your computer when you connect the phone via USB. The problem is obvious, the solution is apparently not. This bug has been annoying users for years and is still not fixed. Since Google focuses on developing the "next big thing"
, many serious bugs take a very long time to get fixed. Obviously these bugs affect only a minority of the Android userbase ... but it's usually the more advanced (or geeky) smartphone owners who "pay the price".