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

https://www.play-bookmarks.win/rtp-and-house-edge-describe-the-game-s-long-run-maths-a-96-rtp-means-a-4

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.