The Marche region of Italy, a great place to take time
Time — there's no substitute for it. Especially for good writing. The kicker, though, is that you don't necessarily need copious amounts of it, but you do need the right type. For writing, especially the editing phase:
Slow down to read and ponder each word — is this really what you want to say? If not, what's the best word to describe it?
Take time away from a piece before returning to edit it.
Take time in a different setting to read your work.
Don't be afraid to let your mind wander to imagine the possibilities for your story. This frees up the imagination to embrace new paths.
Great meals take a bit longer to prepare, but that just makes them more satisfying to savor.