Betting sites determine this number based on the volatility of different games. It is a percentage that shows the betting site return-to-player (RTP).
The RTP of a betting site is also important. It is also important to check whether a betting site has good customer support and accepts payments from reliable sources. Moreover, reputable sites can gain the trust of punters, professionals, and analysts. Often, people who are knowledgeable about online gambling recommend reputable betting sites that have good reviews and ratings. When you visit a betting site not on Gamstop, you should be aware of its legitimacy.