Sometimes you have a rough night in-game. Things just did not work. The tank was not controlling aggro while the mage was over-nuking and the healer was consistently a few seconds late. You had trouble getting a group, then half the people quit and two idiots started arguing about where to go next.
I have occasionally heard about nights that went badly due to one’s own problems. “I’m just not on tonight, guys.” I see that more often with guild-only or -majority groups. When people are with pickup groups, that is when you get the stories about all the other idiots out there.
When it is just us in a group, things are just going badly. We got unlucky, that add came out of nowhere, and the spell did not go off due to lag.
When I am with a pickup group, I am surrounded by morons. He should have known better than to pull those linked mobs, we have the worst healer on the server, and that other guys is half-AFK even when his Etchasketch computer is not choking to death.
You make mistakes because, hey, mistakes happen. You can’t win them all, and sometimes you swing and miss five times in a row for no reason. Other people make mistakes because they are incompetent or they hate your guild and are trying to get you killed. They are probably laughing about it on Teamspeak while calling you a noob.
And then the idiot blames it on you.