I suspect this is true for every writer.
A first paragraph narrates itself while I are weeding the beets or scrubbing the bathtub or cleaning the catbox. And it's very exciting and good, and as soon as possible, after washing my hands, I rush to the desk and sit down to capture it.
I type that great first paragraph.
And the words just stop. Ping. Done. That's it.
There are so many of those saved on my computer. Little bits of a story that never was. So maybe I'll start using them up here.
Whenever she got depressed, she would add 'Kill myself' as the last item on her To Do list. She knew full well she would never get down to that last item on her To Do list. Who does? But she suspected that if she did, she wouldn't feel like killing herself by then. So it was safe, relatively, to add it to the list and fantasize about the moment when her To Do list would be done, and she could make everything finally just stop.
Hm. Well. It probably wouldn't have been a very cheerful story anyway. Or satisfying. Because, just look at it. The reader knows the ending already. Either she never gets to the end of the To Do list, so she never kills herself. Or she does get to the last item, and by then she is so cheered by having finally accomplished her To Do list that she is no longer suicidal.
I think I start about 100 stories for each one that I finally finish.