When my 2006 5th generation ipod encountered a problem last year, I eagerly handed it over to Apple in exchange for the brand new 6th generation ipod nano project [RED] edition. In the store the purchaser focuses on price and appearance and prestige value. At home, the same person will pay more attention to functionality and usability. Our attention is selective in the store.
Second, there is no sound feedback like the click to let you know the action was received. You may accidentally advance further than desired. Then, if you don't use the top button to put the touch screen to sleep and go to clip the ipod back onto your shirt, something might bump the screen. I could go on about how there is no direct way back to the song you are playing in the subgroup from which you selected it (artist, album, playlist, genre). For these reasons the efficiency of the ipod for me was reduced by its advancement.
In his book The Design of Everyday Things, Donald Norman discusses the psychopathology of everyday things from microwaves to stoves and doors, as well as human error associated with bad design. People associate error as their own fault when it's a simple mistake in the design, which leads to that error never being addressed.