Find the Story in the Ending
Often, we don’t know what a story is thematically about when we start writing (“often” meaning 99.999% of the time).
It takes the first draft (if not many drafts) to find what the story wants to be about at it’s core: love, acceptance, trust, conformity, triumph of the little guy, strength of the human spirit, man is animal, etc. And typically, there is one moment in the end that sums up the whole thing.
When the protagonist is at their wits end, sitting in the bed they made, upset that there’s no hope of ever succeeding at what they set out to do, they spend a moment reflecting on what they’ve done, how they got there and what they would’ve done differently or what they wish had happened to them. This may be shown through a full scene of dialogue or by how the main character blinks. Regardless, in that moment, they understand what their journey has been about and connect with the theme.
So, if you are having trouble understanding what your story’s about at it’s core, look to the end of your first draft. You’ve probably written a line of dialogue or presented a poetic visual that sums up what you’ve been trying to say for the entire story. Use that as your focus for the second draft.