Can't Roll for Shit: a gamer term denoting someone who frequently has
bad dice rolls, especially at critical times. Originally used in role-playing games, where the consequence of
bad rolls often means
death for your character.
Many games require rolling dice to generate random numbers so that the results of an action are not foreseeable. Over time, results should be distributed fairly evenly, but someone suffering from CRS tends to have more than his fair share of unfavorable results. In games that are largely luck-driven,
like Risk, no amount of good strategy can overcome CRS. In less-luck-oriented games,
like Monopoly, good play can still sometimes overcome
bad rolls.