Here's the rest.
Tell me you haven’t been here before: You’re about to introduce a character, inject an idea, or just lay down a nice turn of phrase … and then stop. Not because it isn’t good enough, but because it seems too good for now.
You want to save it for later. Later in the same work. Later in life, for another work altogether.
Don’t. Don’t sit on it.
Introduce it, inject it, lay it down now.