Most people think they hate rewriting because they don't know how to do it. The plain truth of it is that inspiration is easy. Writing for an audience is hard. If it wasn't, everyone would do it.
I'd rewrite any time my finished product didn't feel right to what's in my head. I'm doing it right now. If the story's worth keeping, it's worth rewriting. The best advice I can give for a rewrite is first, figure out what's wrong in the big picture and fix that. That way, you're not varnishing your mistakes.
I'd rewrite if an editor or agent asked for it in most cases. Putting aside the writer's ego, reputable editors and agents know how to make your work appeal to the commercial paradigm, and it's in the writer's best interests to listen to them. Only if the true heart of your work is in jeopardy do you draw that line in the sand. Your use of commas, a weak plot or character, or a catchy turn of phrase should not be your hill to die on.
The thing is, if you're serious about writing, and writing well, revision can be a massively educational experience (also humbling, because 99.9% of us--you and me included--ain't all that). You learn more about what makes good writing (and what makes *you* a good writer, along with what you need to work on), and you get better at it, so that next time, your rewrites won't have to be so extensive.
Also, if rewriting a particular story meant I could eat/live comfortably, versus 'impoverished artistic suffering'...you'd better believe I'd get out the red pen. ;)
A close friend who's an excellent writer recommends:
1 Start with an outline
2 Always, always rewrite. Never go with the first draft and plan on multiple rewrites.
3 KISS, don't say more than you must.
4 Find a good editor who is knowledgeable and will give you the hard truth. Brace yourself and accept their tough love when they give you feedback.