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

https://sofiascoolcolumn.rivetgarden.com/posts/variance-vs-volatility-in-slots-are-they-the-same-thing

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.