Revisions are pretty neat if you think about it. With a little planning and determination, you have the ability to give your story a face lift. Freshen it up. Delete an unnecessary character, make another more interesting, beef up the MC's motivation. Add some funny! The possibilities are endless! And that's the problem. When do you stop?
I've heard more than one published author say that once their book hits the shelves, they have a hard time even thinking about reading it again. They know they'd find more things they want to change, even though they've already read it through countless times, making it the absolute best they could. There's always something you're going to want to change about your own work. We are our own worst critic, after all. But at some point, you've got to stop obsessively reading over it. Trust yourself that you've made the right decisions by your characters, that you've caught all the pesky typos and out of place commas that you can (let someone else find the rest--sometimes it takes another set of eyes) and send that puppy out into the world! (can you tell I just did another round of revisions this past week?)
Have you done any revising lately? When did/will you say when?