Snip, snip, here, snip, snip, there...
I have that song from The Wizard of Oz running through my head a lot these days as I revise the second draft. Once again, I'm finding what I refer to as pointless off-shoots - little bits of dialogue or characterization or plot that might seem to be leading somewhere, then don't.
That sometimes means cutting some bits that I quite like. This is never easy, but since I feel it's necessary, the cuts are made.
That's one reason I do so many drafts. With every draft it becomes clearer what is necessary in terms of story and character, and what's not.