Just to add on to the topic of "That's why people are leaving and rejoining a lobby" I'd like to say that another reason why donors in particular might leave and rejoin is: they join the server, sees maps they don't like, then leave. Then they rejoin that same lobby because they couldn't remember if they had already joined that lobby before. I've done that many times where I join a lobby, leave, then accidentally join the same one. I'd just like to say that before a few donors (such as myself) are accused of abusing this glitch.