Martingale

The Martingale is a negative-progression betting system in which the player doubles their stake after every loss. The logic is that the first win recovers all prior losses and yields a profit equal to the original stake, because the doubled bet at last covers everything risked plus one base unit. It is most often applied to near-even-money casino bets such as red or black in roulette. Worked example: starting at a 10 base bet on an even-money proposition, a losing run forces the sequence 10, 20, 40, 80, 160, 320, 640, 1,280, 2,560, 5,120. After ten consecutive losses you have staked 10,230 in total, and the eleventh bet required to continue the system is 10,240 — all to net a 10 profit if it finally wins. A run of ten losses is far from rare over a long session, and it collides with two hard limits: a finite bankroll and the table maximum. Why it matters: the Martingale feels almost foolproof because short sessions usually end in a small win, which lulls players into trusting it. In reality it trades many small wins for the occasional catastrophic loss, and it does nothing to change the underlying house edge — over time the expected result is still negative, only with far greater variance. The mathematical flaw is that it assumes unlimited bankroll and unlimited stakes, neither of which exists, which is why it is a reliable route to ruin. From a responsible-gambling standpoint it is best avoided entirely. See also negative progression, house edge and bankroll.