when a player disconnects during a game, it is most likely out of cowardice, however there is at the moment no way that you can tell if they disconnected for a genuine reason or not, and it is likely that there never will be a method of telling if they had a good reason for quitting or not. I don't think it is right for punishing somebody just for disconnecting ingame during a match, however if the player was proved to had disconnected just because they were losing then it would probably be fair to award them some infraction points on the forum. This will probably never happen though, as you cant tell why a player disconnected.