Okay... I have absolutely no idea. But I just spent two hours at a Little League game, I should be able to come up with some analogies.
1) Sometimes you hit it out of the ball park. Sometimes you strike out -- When writing, some scenes can really blow you away, and other times it feels like your writing a grocery list (in other words, not exciting at all - at least my grocery lists aren't exciting)
2) Sometimes you do everything right, but the team gets an out anyway because the coach does something stupid. (Okay, I'm not sure how this relates to writing at all, but our team got an out because the coach helped up the player who had slid into third - can't touch the players). For a writing analogy - you could have a great story that you've perfected over years - but by the time its all ready the market is saturated (vampires, anyone - though I'm not sure we've reached saturation there)
3) Don't throw the bat. If you have a great hit, but you throw the bat you're out. If you write a great story, but get an agent's attention for the wrong reasons (I don't know, like stalking or something) you'll probably lose out on a sale.
So - there are my very lame baseball/writing analogies. Anyone have anything better?
And our team won the game (by one point, despite three outs for kids throwing bats and one out for the coach touching a player).