The probability that, given a certain bankroll, a gambler will be ruined. For video poker, the Risk of Ruin is generally computed for an infinite number of hands, since the computation easier, though it can also be computed for any number of hands. However, if the number of hands is not specified, it is assumed to be infinite. The (infinite run) Risk of Ruin is always greater then zero for video poker, including positive games, since the variance is always non-zero. For all negative expectation situations, the Risk of Ruin is always 100%. That is, regardless of the bankroll, a gambler who plays a bad game will eventually go broke. The Risk of Ruin decreases as the size of the bankroll in betting units increases. Hence, decreasing game denomination (unit or wager) at a fixed bankroll decreases Risk of Ruin.
See also: Survivability.