100%. I think the issue for most writers (at least at the moment) isn't 'where do you get an idea?', it's 'where do you get the time & energy to fully work it through?'

It's cold, that's good enough for me!

Yeah, while fanfic can't teach you everything you need to know about writing original fiction, it can definitely teach you some things.

(And also, writing fic filled a whole different psychological need than writing my own stuff! It did me good at the time, it didn't have to be training wheels.)

Mostly angsty character studies and hurt/comfort, but also one uncharacteristically epic SF crossover that I credit with teaching me how to plot.

Oh man, I loved this book soooo much when I was 12