RTP is a long-run return; the house edge is the casino’s statistical share: 96%...

https://stephensexpertword.publishlane.com/posts/what-s-the-difference-between-volatility-and-risk-for-a-slot

RTP is a long-run return; the house edge is the casino’s statistical share: 96% RTP = 4% house edge. Volatility affects how wins and losses arrive. In a short session, results can be far from the average—RTP doesn’t guarantee a payout.