One of my father's favorite proverbs (he said it was a Russian one, but I don't know if that's true) was:

Don't let the "perfect" stand in the way of the "good."

I think he first heard it in the context of trying to reach a satisfactory arms treaty with the Soviets, and the dangers of rejecting proposal after proposal because it doesn't meet every single one of your objectives. But I think it can apply to any creative endeaver (and finding romance, cooking dinner, and cleaning house, and raising your children, and....) and certainly echos what Marion said, above.