That’s bloody hard! If you look at any great piece of art it’s the editing that makes it magical. It’s what you choose to show and what you choose to wipe out. I just wiped down a piece I have 20 hours in to because it was getting too fussy. I love that about oil paint - until it's dry and in someone else's house it's transient and subject to sometimes fierce editing. As an artist, you have to be ok with that. Try not to become so attached to what you have managed to get onto the canvas that you can’t sacrifice it to the greater vision for the piece.
Shall I get a wee bit cheesy and say that life is like that too?