But it wasn't always that way. When synths first came along in the late 70's, every sound had to be programmed, requiring a skill set by the average keyboard player that might stagger the players of today. All the parameters that are instantly accessed today by a touch of a button had to be individually programmed, which required both time and skill (this is where the term "programmer" first came into being in terms of keyboards, since major acts needed one to program the synth between songs).
As an example of how far we've come, here's a video from 1980 where Dr. Bob Moog (inventor of the synthesizer and founder of Moog Electronics) gives a demo to the BBC.
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