After running a Shadowrun campaign for five years in my home state, I was jonesin' hard for Shadowrun when I moved to the Bay Area. Eventually I was contacted through AccessDenied by a perfectly nice and -- as gamers go -- normal guy. As is my habit, I asked if it'd be possible to meet the GM (and maybe other players) first, to talk about gaming and get an initial reaction as to style compatibility. I should've known something was up when only the original player showed to our agreed meeting, but I needed my Shadowrun fix, and that player was okay, so I figgered I'd give it a try.
What followed were 18 to 20 of the most excrutiating hours of my life. There was the GM, myself, and two other players. The players seemed pretty normal, except very easily distracted. (They spent a lot of time on the PlayStation.) The GM, though ...
First, he had no prepared material. Zero. Not so much as a page of notes. Not even a pencil and a page to make notes.
Second, he had no grasp of the rules of Shadowrun. He would simply make rules up, although if any of the three of us told him what the actual rule for a sittuation was, he'd accept it amiably enough.
Third, and worst of all, he would just ... zone out. He'd start to narrate, or describe, or play an NPC, and then ... he's just trail off quietly and grind to a stop. He wasn't in a trance, or having a petit mal seizure, or anything like that, because he'd do things like flip through rulebooks or roll dice. It was like he just sorta forgot he was talking. This would go on for at least a minute -- longer if one of the players didn't prompt him -- and it happened at least 10 or 15 times an hour. I can't overstate how bizarre a situation it was, and yet the other players didn't even seem to notice.
So, after about two hours of this, I was determined that I wouldn't be coming back. The problem was that I'd loaned a book to one of the other players, and since he seemed like an okay guy, I wasn't confortable rescinding the loan. So I went back for another session, but he'd left the book at school. So, yes, I went back for another session, but solely to reclaim my book; I didn't even take my jacket off, citing time issues as the reason I wouldn't be returning. They were all vaguely shocked that I wouldn't make their game a priority.
Man, that was odd.
I left a D&D game once just because the commute was too much. It was a decent game, but it was a total of 2.5 hours on BART for a four hour session.
I know for a fact that I drove away two players from a couple of games. The first time, I jokingly remarked a couple of times on how incredibly long one player's fingers were. (They were, I swear, like a full two-thirds the total length of his hands.) It was the kind of joking most people laugh about, but apparently this guy was particularly sensitive about his long fingers. He never came back, and I didn't find out it was because of me until almost two years later.
The second time, when I shared that I occasionally trimmed my cat's whiskers to curb a certain behavior -- with knowledge of my vet -- the guy became adamant that I was "torturing" my cat. Since I absolutely adore my cat -- and vice-versa -- I was a tad miffed by that continued assertion. Since I'm 6'5" tall and built like a dump-truck, I'm a little bit intimidating when I'm miffed. He missed the next session, then dropped from the game. I sorta regret that one, because aside from being an idiot, he was a great D&D player. A dedicated gamer with good knowledge of the rules, and a good roleplayer. Ah, well.