Let's get it all off our chests today -- what's the worst PuG experience you've had? Even worse, was it your fault?
Probably the worst re-occurring PuG nightmare I run into is the kamikaze mage. She thinks she's invincible, she decides she wants all the mobs' attention on her, and as a druid I have to judge whether to keep her alive or try to get aggro myself. Neither usually works. I know I've been guilty of playing my class badly, especially when new to a class or rusty after playing others for a while, so I expect I've afforded as much amusement to others as these have to me.