A session ends after 2 hours without a bet. “Expected” is what you bet times each game’s house edge (with perfect strategy), so it’s the price of the entertainment. Luck is the gap between that and what actually happened; it averages out to zero, the price doesn’t.
Set a loss limit and a time limit. Every game checks them after each bet and tells you once per session when you hit one.
Martingale and friends change how you lose, not how much. Run thousands of sessions and see.
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