I used to keep a writing journal. In it I'd put story ideas, consider problems I was having w/ longer stuff, give reactions to great shit I was reading, etc.
I still have it but don't write in it any more. One possible reason: I have less time. Another: I write less longer stuff. Another: I don't have as many problems.
Maybe my favorite: lately most of the stories I write don't come from story 'ideas.' The Gymnos were probably key in this. Only one of them -- out of the forty-some -- came from an 'idea,' something I might have written down in advance. Since none is longer than 200 words, that seemed obvious -- to have them come during the composing.
But lately, writing slightly longer stuff, I've been doing the same thing. I've noticed this: if I write a story of 700 words that way, it feels to me like fifteen hundred afterwards, after I read it. No clue why that is.