I GMed a wee bit in high school, and I sucked at it (I sucked at playing too back then so it's all good). Then I had a long, long dry spell through college and into adult life. Past two+ decades I've mostly been a player (3.5e, 4e, Spirit of the Century, BRP, ORE, Torg Eternity, Torchbearer 2, Blades in the Dark, Stonetop, a few others). Last year I started GMing Torg Eternity for my regular group, to give our poor GM a chance to play. I hated it at first. Just hated it. So prep intensive (we're on roll20, but even in person it would be a chore), and the rules I thought I knew well as a player turned out to be such a mess when I had to adjudicate. I worried about screwing up, I had a player or two lose their temper briefly on some ways I handled certain actions, even though they knew I was new at this, and was generally not liking it a bit. I wrote an initial mission myself, then modified a short one from the sourcebook set I backed, and now am running the big "adventure path" from that same set. I wrote a little bit of homebrew supplemental material for that (the equivalent of new feats and such, changes to handling spiritual corruption), encouraged the players to play at least one native to the realm they were adventuring in, not a one of them did, and they ignored my supplemental material. Hrmph.
Then, at some point I stopped caring so much about being on top of everything, or about the players all making total aliens to the setting and ignoring the stuff I'd made up (and hoped to playtest!). Although the VTT prep still sucks, I just breeze my way through the adventure and the gang still has fun riding the railroad and seeing the sights. If I screw up, I say so, rewind or retcon, and nobody's feathers get ruffled. And I have abandoned any idea of publishing any material for the game because it's just never going to get any feedback.
I recently got to try Dogs in the Vineyard and would
love to GM that someday. In the meantime, I am hoping to find another group to be a player in. Even for Torg Eternity, which I had grown to hate so much for a while, for reasons mentioned above and more. (I'm on the west coast, hit me up and see if we can schedule it.

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