Ever since roulette has been around, there have people that have tried to beat roulette. Most have ended in tears but some people have been successful.
The successful ones have all exploited some flaw in the roulette table or used some machine to predict where the ball will land.
The flaws in the roulette table aren’t around anymore. Many years ago, roulette tables were made differently and some were biased. If you recorded enough numbers, you could see biases in the wheel. Some people successfully exploited this. With modern wheels its impossible though.
The most famous people that used the bias wheel were Gonzalo Garcia-Pelayo, who won over a million euros using biased wheels in the 90s in Madrid Spain. Also, Norman Leigh who wrote a book called 13 against the bank. He used a Reverse LaBouchere system on biased wheels to break the bank in Nice in 1966.
The other successful people that have beaten the roulette table are those with devices to measure the speed of the ball at certain points during the spin and use that to over turn the house edge. The most famous were an eastern European gang who made £1.3 million from the Ritz in London in 2004.
They were arrested, questioned and eventually released as they had no broken any laws. The didn’t interfere with the roulette wheel. They got to keep their winnings.
All regular systems based on progressive betting are doomed to failure in the long run. This is because of the house edge. The presence of the zero makes the game slightly favour the player. The house edge for European roulette is 2.7% or 1.35% if playing even money bets with la partage rule. Over time this small edge depletes the players bankroll.
Its a matter of when rather than if a system will fail. The system just changes when the likelihood of bankruptcy is. For example, playing on the inside or outside, the odds are the same but the variance in results is more when playing on the inside. Wins are infrequent but big whereas on the outside wins are more frequent but smaller. The same is true on the systems you use.
Systems usually involve varying the stakes after wins or losses. Some systems may work well in the short term and if you are lucky, you can walk away with profit. Systems all come undone because of the bet limit and players bankroll. If a player has a large enough bankroll and the casino allows a large spread from the minimum to maximum, you can actually beat the casino.
Below are some of the more common roulette systems. Thanks to wikipedia for the bulk of the content.