The little tidbit that inspired you to write in the first place? That gimmick, that first-liner, that obsession – you could simply put it aside or revisit it. But the most important thing is that you stick to the treasure you’ve found.
It might take awhile to get to that treasure, but once you’re there, you’ll know that it’s what the entire story is about.
It could be a message. It could be a vision. It could be something as fleeting as an emotion.
But that treasure is the diamond in your book, it is your crown jewel. You need to protect it, and not let anything distract your readers from it (not to be confused with a plot twist; if anything a twist should bring the readers closer to the treasure instead of away from it).
If it means letting go some elements that you loved about your story just so that your treasure can be more prominent, then you must do it. That’s when editing comes in. Make sure that you guard that treasure. Every word that does not aid the reader in finding that treasure is a wasted word; snip it off.
Be meticulous, be merciless, but keep it magical. The treasure is above all.