>How many of us would use a music player that just had start and stop buttons?
Two words: iPod Shuffle. Or, if you want a slightly more complicated example, Pandora. Pandora literally started out with three buttons: "I like it", "I don't like it" and "Stop". Recently, they added a fourth, "Skip".
No: if you double-click, triple-click, and (potentially in combination) hold that button you can do all of the normal things you can do with a media player. Go read the user manual. People who believe otherwise (and I've seen many) simply assume user interfaces don't exist if they aren't obvious.
Two words: iPod Shuffle. Or, if you want a slightly more complicated example, Pandora. Pandora literally started out with three buttons: "I like it", "I don't like it" and "Stop". Recently, they added a fourth, "Skip".