Maybe you play a melody twice. You play it once like you like it, and some parts that you don't like you can just switch. An eight-bar motive - you can just take it and put it in the front or back or something like that. It can save you 50 or 60 or 70,000 dollars, a drum machine. That's why everybody uses it.
Miles DavisI can hear what I want [people] to play. If you don't hear what you want someone to play, then you can't tell 'em.
Miles DavisSometimes [playing free] doesn't happen, because maybe a guy's wife'll come in, you know, and his ego will catch him. If everybody's completely just straight-without any old ladies over here, a fourth of whisky over there; if it's balanced right, it'll come off. It has to be. But when you get egos involved with playing free, you can't do it.
Miles Davis