Fiction Thursday: "The End"

I had a professor in college who never gave 100% on papers. She told her students this on the first day of class, and explained that the reason is because she believes there is always room for improvement, and a score of 100% means the assignment is the best it can be.

I understand her logic (not sure yet if I agree with it). And this is something that plagues many writers: when, if ever, is something its best? When are you done writing it? And I don't mean "done" as in "the story arc is complete". I mean "done" as in "there is nothing else that can be done to this story to improve it".

There have been many times I've written something, edited it, and been happy with the result. And when I go back to read the "finished" product, I find myself scrambling for a pen to make more changes.

Maybe those changes really did need to be made. Maybe I'm too critical of my own work. Either way, there are many pieces I've written that, even after they were out of my hands, I didn't feel they were done.

Part of me thinks it's because creative writing is so subjective. It's not like mathematics in which solving for x means you're done. In creative writing, different people have different opinions, and there's always someone who has suggestions for improvement.

So how do you know when you can let go of a piece and start working on something else?

A friend of mine told me she considered herself done when she read through the piece three times without making significant changes. (I'm not sure what her definition of "significant" is, either.) Someone else I know says he's done when the piece has been submitted. (How he knows when to submit is beyond me.)

What about you? When do you feel you can be done with a piece? What criteria do you have for the transition between editing and submission?