Some of the PRs I submitted were pretty dumb and a complete waste of someone's time to review/reject but they showed enough patience to help me get "over the hump" and to eventually get commit access to the repo -- which didn't really help with getting features implemented because I have an apparently unlimited supply of dodgy ideas and would get "why is this needed?" a lot. I also had a habit of getting code to about 80% there before doing a PR "for discussion" knowing full well the lead maintainer would fix up the remaining 20% if it were a valuable enough addition.
Probably also helped that the project has a history of working with GSoC students and the devs were a generally helpful bunch with getting new contributors up to speed on the codebase.
Honestly, if they weren't so welcoming I'd be half the halfassed-coder I am today.