At this moment it is only my personal experience. I believe on new games. To attract new customers an algorithm is set on a higer % win ratio. As time goes by this is reduced. It really stood proud to me this week when playing Piggie Riches..3 pigs , which sets off the wheel, where far fewer. As and when finally achieved the prizes were less. Big wins occurred far less and when they did, they were not great. Meanwhile new games were playing well.