Stockfish is incredibly strong at exploiting small mistakes. I’m going to assume that on average if you make anything other than the top 5 moves at any point in a game, stockfish will win, no matter what you do after.
An average game is about 40 turns, and there’s about 20 valid moves each turn.
So that puts a upper limit on success of 1 in 4^40.
Similarly if you pick the best move at all times, you’ll win, putting a lower limit at 1 in 20^40
Making some assumptions about how many best moves you need to counteract a poor but not fatal move, you could try to estimate something more accurate in this range.
If you want a more accurate estimate of how often top chess engines pick the theoretical best move, you could compare Leelachess and stockfish. These are very close to each other ELO wise but have very different engines and styles of play. So you could look at how often they agree on the best move, and assume that both have some distribution where they pick their best moves from the the true move ranking, and then use that to calculate parameters of the distribution.
Stockfish is incredibly strong at exploiting small mistakes. I’m going to assume that on average if you make anything other than the top 5 moves at any point in a game, stockfish will win, no matter what you do after.
An average game is about 40 turns, and there’s about 20 valid moves each turn.
So that puts a upper limit on success of 1 in 4^40.
Similarly if you pick the best move at all times, you’ll win, putting a lower limit at 1 in 20^40
Making some assumptions about how many best moves you need to counteract a poor but not fatal move, you could try to estimate something more accurate in this range.
If you want a more accurate estimate of how often top chess engines pick the theoretical best move, you could compare Leelachess and stockfish. These are very close to each other ELO wise but have very different engines and styles of play. So you could look at how often they agree on the best move, and assume that both have some distribution where they pick their best moves from the the true move ranking, and then use that to calculate parameters of the distribution.