RTP is a long-run average; the house edge is the casino’s expected share: 96%...
https://shanesexpertthoughts.capitaljays.com/posts/how-do-casinos-calculate-rtp-is-it-really-millions-of-spins
RTP is a long-run average; the house edge is the casino’s expected share: 96% RTP = 4% house edge. Volatility affects how often results swing and by how much. In a short session, luck can overwhelm the averages, so outcomes may differ sharply.