Throughout history individuals have claimed to discover a “system” to beat roulette. For hundreds of years these systems have been “re-discovered” and tested-and many of them amount to sheer folly. They have exotic names like Fibonacci, Martingale, D’Alembert and Labouchere. They all involve increasing your bets as you lose-primarily on the even money wagers like red or black.
Martingale is keyed to doubling your wager after each loss until you finally win. When you do win, you’ll only be one unit ahead. When it comes to D’Alembert, it’s a technique related to increasing one unit of wager each time you lose and cutting back a unit when you win.
Whatever the system, the weakness is that you must risk large sums of your bankroll to win one single unit. You’ll hear of others like the Reverse Labouchere (also called the Reverse Labby), where you’ll be increasing your bets continually until you reach the house limit.
In modern times, players have searched for “biased wheels” where some defect in the wheel itself creates an edge because the ball seems to fall in a certain “sector” more often than it should on a random basis. This apparent bias allows an edge to alert players and most modern casinos are well aware of disastrous consequences of using a biased wheel and constantly guard against it.