Sometimes you'll win at slots, and even win big. Enjoy those times when they come. But never bet money you can't afford to lose, and be sure you're playing games that fit your bankroll. As a basic rule of thumb, your gambling bankroll should cover 250 bets to give you a 90 percent chance of lasting three hours.

Key Takeaways. Gambling is not a good alternative for earning extra cash. Each game you play at a casino has a statistical probability against you winning. Slot machine odds are some of the worst, ranging from a one-in-5,000 to one-in-about-34-million chance of winning the top prize when using the maximum coin play.