From James Grimmelmann’s “Life, Death, and Democracy Online“:
… The necessity of a ‘Quit’ option is obvious; no adventure game yet invented can force an unwilling player to continue playing. She can always give the game the three-finger salute, flip the power switch, or throw her computer in the junk heap. …
Banishment is the absolute worst punishment any multi-player online role-playing game can impose on a player. Which is to say that a painless execution is the absolute worst punishment any game society can impose on the characters who are its citizens. Torture is not an option. Imprisonment and fines can be imposed, true, but as soon as the player behind the character finds that these punishments are too onerous, she can simply terminate her account and stop logging in; the rest of the deterrent value of the punishment evaporates. It’s hard to hold characters accountable.