Example: I [stupidly] bought an iPod without realizing how it would interface with my Windows machine. I assumed that it would work just like the cheapo $20 MP3 player I had bought for my 10 year old niece. But no, dragging files to a mounted drive is much too plebeian for Apple. Apple requires iTunes, since it's better at "organizing" my music, even though I have never bought anything from the iTunes Music Store. I tolerated iTunes as long as I could, but I eventually needed my own podcatcher software and iTunes was getting in the way of dumping files onto the MP3 player. One of the most satisfying days in my life was when I installed Rockbox on my iPod and was then able to remove iTunes from my system.
I'd like to try an iPhone as well, but I don't think that I could stand the constraints on that either.