Update: posted 100 of my own prompts in 100 days and got more from 3 of them than from any writing class
I finished day 100 last Tuesday. The 3 that actually turned into stories came from prompts I almost threw out: a grocery list, a wrong number voicemail, and a gym locker someone left open. Here is the part people push back on, I think working from other people's prompt lists is mostly wasted time. I spent about 40 hours on borrowed lists before this and finished zero drafts. When I write my own prompt, I already know the scene, so the page fills up fast. My honest take is the prompt matters way less than who picked it. What did you get out of the last prompt you wrote yourself versus one you copied?