In my case, at a "startup" (it isn't) I was offered the non-compete, with extremely nasty and broad language that unfortunately is enforceable in Texas, 3 months after I had been working there. You can imagine the coercive effect of that one: sign this or look like you got fired at 3 months. I was able to negotiate some changes to the broad clauses, which by their own admission were cut-and-pasted from somewhere else, but it made for an appalling experience.