It just plain does. One of the things that's kept me away from this blog, beside attempting to actually live my life, has been a long spate of rewriting, which always just leaves me drained.
I'm a big fan of first drafts, a huge fan of first drafts. They're fun and exciting and it's all juggling flaming chainsaws. I tend to be a Stewer, as a writer: I stew, I simmer, I think and ponder. I've spent up to two years just thinking about a play I want to write. Not constantly, but coming back to it, writing scenes in my head, working out plot points and themes, kicking it around for as long as possible, until finally I sit down to write. The first draft usually comes quickly. I've heard Edward Albee speak about writing like this, that he finds himself "with play" and then the play springs fully formed from his head. I ain't Albee (in so very many ways), but that's pretty close to how it is for me.
Which makes rewriting a long, hard slog. If first draft is juggling, rewriting is dancing in mud, it's cleaning the bathroom, you name a hard, difficult task that most be done. And it's got to be done. First drafts can get by on adrenaline, style and dumb luck. To make the crossover to a play, you need to tighten your structure, kill your darlings and rethink what you've done. And good luck doing that once you've gotten even well meaning notes.
So I've been trying to rewrite two full-length plays for various deadlines and it just kills me sometimes.