The Martingale Doubling Strategy is devised for wagers that pay even money. This is primarily the reason it is linked with the ‘red’ or ‘black’ bet in roulette. The strategy is simple and easy to execute and is popularly adopted by novice gamblers, wherein the amount won is equal to the amount initially wagered by doubling the wager at each loss. For example, if a player bets $1 on red in his first bet, he will get back $2 if he wins and thus will eventually win $1 after deducting his initial bet.

In the event of losing, he will double the bet and bet $2 on red and his total investment thereby will become $3, and in the event of him winning he will land up getting $4 and again in effect would win $1. A ratio of 1:3 wherein winning 1 for a deposit of 3 looks fair, but in the unfortunate event of him losing the second time he will have to bet $4 on red making his total deposit $7, so eventually he will win only $1 at the end. This would be the pattern for seven rounds where his total investment would be $127 and he would then have to bet $128 taking his investment to $255, and eventually the same principle applies of having won only $1 overall.
Novice online roulette gambling players are of the opinion that if the spin of the wheel has resulted in a series of black numbers, then the chances of the next number being red are very high. However, roulette is a game of chance and the wheel has no memory and at every spin of the wheel there are 50% chances of both red and black emerging.
The Martingale strategy is not highly recommended as it eats up bank roll at a voracious pace, and if you look at the overall statistics to win $1 a player needs to invest $257 and if he wishes to win $10 he should be prepared to invest a huge $2750, averaging at $350 per bet which does not look a logical proposition at all!