The Return to Player (RTP) percentage, which shows how much of the total amount wagered a slot machine is designed to return to players over time, is one of the most important varrummy rani apkiables. In general, players looking to increase their chances of winning are better off playing slots with higher RTP percentages. When a slot machine has a 96 percent RTP, for example, players can anticipate getting $96 back for every $100 wagered on average. Variance & Volatility. The volatility or variance of a slot machine is another important feature.