- You leave a game while playing a Mann Up game on an official server; and
- You have not played through a single wave to completion or failure; and
- There are 5 or more players currently connected to the server (including you).
Otherwise, it is safe to disconnect a game without being considered an "abandoner."
Q: What happens if I "abandon" a game??
At first, nothing. (Sometimes you lose your Internet connection and cannot get back online to rejoin. And sometimes, you just have to go.) Penalties will be imposed on players who repeatedly abandon games. These players will be temporarily placed in a low-priority pool and will experience longer matchmaking times.
Q: If I'm thinking about leaving a game, how can I tell if I'd be "abandoning" it??
When you press the Disconnect button on the Main Menu, a prompt will confirm one of three things: that you are not abandoning the game and that it is safe to leave; that you are abandoning the game but will not incur a penalty; or that you are abandoning the game and will incur matchmaking penalties by disconnecting.
Note that leaving a game by pressing the Disconnect button ensures that you will never incur a penalty without prior warning. However, if you disconnect through any other means, such as typing "disconnect" or "quit" on the console, or by accepting a Steam invite, no prompt will be displayed, and you may incur penalties without being notified.
Q: What if I crash or lose my connection??
If you crash or lose your Internet connection, your spot on the game server will be reserved for you to rejoin within three minutes. If you do not rejoin within three minutes, you will be treated as if you had quit the game intentionally.
After a crash or loss of Internet connection, restarting TF2 will give you a prompt to reclaim your spot. This prompt will also tell you what (if any) penalties you will incur by declining.
If you meet the abandonment criteria outlined above ("What is "abandoning" a game?"), AND if you fail to rejoin either because you let three minutes go by or you declined the prompt, then you are considered to have abandoned the game.
Q: What if I get kicked for idling??
If you are automatically kicked due to inactivity, you are considered to have quit intentionally. You may be considered to have abandoned the game if the other abandonment criteria ("What is "abandoning" a game?") are satisfied.
Q: What if I'm vote-kicked?
If you are vote-kicked by other players, you are not considered to have quit intentionally and will not be considered to have abandoned the game.
