Well it depend, players get kicked for 3 reasons:
- Slots are reserved for somebody else. (Yes there is something like priority, like it or not it's in our right.)
- Teams wouldn't be balanced.(Like Matt said.)
- The player has a reputation for being a troll, ruining the game. (Quit, happy building hour, not communicating...)
You usualy got kicked for reason 1, wich made some players realy upset.
But what does it matter?
People will never like to be kicked and so keep complaining about it,
so don't be all like ''Yeah pro players are so mean.'' and then ''Pro sounds so stupid.''
But hey I don't see here where anybody called himself pro,
people actualy use it now as a term for people who they can't play with.
As long as you don't get insulted, (noob is not an insult,) people do in their lobby what they want.
Are we cool now?
Kick fast, think Bo.