RTP describes the share a game is designed to return over time; 96% RTP means a...

https://www.quantifiedstrategies.com/rtp-variance-and-expected-value-applying-a-quantitative-framework-to-online-casino-gaming/

RTP describes the share a game is designed to return over time; 96% RTP means a 4% house edge on average. Volatility affects how wins and losses are spaced. A short session can vary widely, so actual results may be far from the average.