40th D&D - Lessons of D&D

Day 28: What's the single most important lesson you've learned from playing D&D?

Self-confidence.
I am good at D&D. I can build strong characters with rich stories and role-play. I can min/max with the best of them. I can write engaging plots that people want to play.  I can keep the players guessing and surprised. I can sell my rpg ideas to other people.
Sure, I'm not the perfect D&D player (I have an article in writing that details all the ways I am a horrible DM, but that's for another day), but I pretty good at it.

Who cares, it's only a game. 
Because I can bring enjoyment to other people's lives. No, I can't make their everyday depressing lives overall better, but for brief moments they can have fun...and I had a hand in that (along with the rest of the group). But it's not about being good at a game, it is about being good at something. Too many people go through their lives never being good at anything.

That self-confidence carried over into things such as work or other activities. It's not that I learned some skill from D&D that I could apply to the other things. No, it was simply knowing I could do something well; that let me think I could do other things well.