There’s a binder stuck in a drawer with the first draft of what would ultimately become The Daedalus Incident. It’s covered in red copyedit marks and is altogether not-good. But I’m keeping it. And more importantly, I’ve kept every draft of everything I’ve written.
Why? Because even if the overall draft is bad, there may be parts in it that are good. I know this seems like common sense, but I think it’s worth mentioning.
There was a whole sequence of events in The Enceladus Crisis that ultimately didn’t work. The pacing was off, the timing was wrong, the characters just weren’t ready to go do what they were doing. But I knew there would be a time within the narrative where all that hard work, primarily in worldbuilding and plot, would be necessary. So I slapped it in another file and kept going.
And when I reached the point in the draft where that worldbuilding and plot came to the fore, I gleefully cannibalized that older version to suit my needs.
There’s a couple of scenes in the early Daedalus drafts that I’m keeping handy, just for that purpose. It’s highly unlikely they’ll be dropped straight into a future work, but there are writing lessons in there, and some ideas that may yet be used.
The point is, don’t overwrite your old files. Save them and store them. It’s not like Word (or Scrivener) files are that big, after all.
They say “kill your darlings,” and at times, that’s exactly the right thing to do. But be sure to keep the bodies handy. You never know.