I think I can count on one hand the number of times I've been allowed or asked to really impact someone's RP in a seriously meaningful way, and the outpouring of thanks I got from that had me taken aback.
Someone came to me in last couple of days, their character looking to ask mine for advice and possibly direction. I, who am not exactly used to playing a leadership character in any serious way, agreed but internally I was seriously worried about not being able to help. Or worse, my help wouldn't be all that helpful.
During the agreed upon scene, I ended up paging a few other people asking for my own advice and spitballing ways that would make future RP for the character that came to me meaningful and enriching. The idea I came up with was refined by the people I spoke and once I set down what I thought they should do, after the scene they said they were very thankful for it.
I don't get that feeling very often. That sense of reward and accomplishment in doing something beneficial. Or at least, I don't hear about it. I'm really happy I was able to foster character development and good RP for another player.
That is, to me, one of the few reasons I still stick around this hobby.
