On the site formerly known as Twitter, I'd occasionally use it as intended and throw out something short and quippy. More often than not, I'd wind up with threads of me meandering as I found my idea.
This isn't just shouting out how useful drafts is, no. The best feature here is that I can complete a train of thought, look at it all, and then decide not to post any of it.
Sometimes, it becomes a rough draft where I realize I'd wandered off topic and need a stronger conclusion. But frequently I'll just find I needed to write my idea out... And no one else needs to see it now.