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I wonder if it was the basic gambler’s fallacy- which to be honest I still can’t grasp. I fully understand that conceptually every roll is completely independent and red/black is always ~50/50, but it’s very rare to see 20 straight black rolls in a row. Can someone try and explain it (if there even is anything to explain)?

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Easier to explain with coin flips. Let’s say we do 100 flips - we know the “most likely” thing to happen is 50 heads and 50 tails. The actual probability of that is C(100, 50) / 2^100 = 0.079.

So about an 8% chance. You’re significantly more likely (ie 92% chance) to see _something else_. And that’s _the most_ likely outcome.

So tldr - it’s not so much that “you never see an all tails sequence in practice” - you’re actually unlikely to see any particular sequence. All the probabilities get astonishingly low very quickly.

Another point is that roulette is never 50/50 for red/black (there are 0, and sometimes 00 which are uncolored)

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