400,000 hands played and preflop mistakes

2024-08-26

Recently, ActionFlop crossed a milestone: 400,000 hands played by users against the GTO bots. These hands have been played by 4,200 users over hundreds of hours. In the aggregate, the data is quite interesting to look at, and there is a lot to learn from it.

If you have played poker on ActionFlop, you know that you can play poker hands against GTO bots. GTO bots play a Nash equilibrium strategy which is approximately perfect. Humans play imperfectly. They make mistakes. A mistake happens whenever a player chooses an action which the player should never choose according to the GTO strategy. For example, if the GTO strategy is to fold 0% of the time, call 40% of the time, and raise 60% of the time, then folding is a mistake. Any time a mistake is made, there is some loss in expected value (EV), which is gained by the other player (in heads up poker).

Over the last 100,000 hands with GTO bots, humans made 39,116 mistakes, and those mistakes cost 96,256 in total EV. Since the big blind is 2, this amounts to a loss of 48.1 BB per 100 hands. You may be curious to know what kinds of mistakes humans are making. After all, if you can figure out where you're making mistakes generally, you can start to try to correct them moving forward.

To begin to answer this question, I divided the game tree into situations and then sorted the situations by total loss due to mistakes. For example, one situation near the top of this list is "Preflop Single-raised; Flop Check-Bet-Raise (BN)." This means the button makes a lot of mistakes in single-raised pots that go check-bet-raise on the flop.

Out of the top 10 situations, 8 out of 10 are preflop. The number one situation is "Preflop Single-raised (BB)." This situation accounts for 5,593 in total EV loss. That amounts to 2.8 BB per 100 hands.

This highlights the importance of getting preflop decisions right. When it comes to learning how to play a GTO strategy postflop, you generally aren't going to be able to memorize charts. You're hopefully going to pick up on patterns by looking at charts, but you're not really going to be able to memorize the billions of charts you could look at for postflop play.

Preflop is another story. You can, and should, memorize preflop charts. Whether you're a visual learner or not, you can see that there are patterns to preflop charts that should help you commit them to memory. Start at the top of the game tree with open raises, then move on to 3-bets, etc. The benefit of doing this is that you're going to have a much better sense of where you are when you get to the flop. You can think more methodically about how your range — and your opponent's range — interacts with the flop, turn, and river. Maybe your gut instinct will help you out, or you will be able to act on patterns you have picked up on consciously or unconsciously over the years. Maybe some of the time that will lead you to the GTO choice, but it won't be the result of a consistent, methodical, strategic way of thinking. Without that strategic thought process, you don't have much hope of avoiding mistakes.

With that rant out of the way, let's look closely at the top mistake situation: "Preflop Single-raised (BB)." To avoid mistakes in this area of the game tree, we only have to look at one chart, the BB's response to a single raise:

A
K
Q
J
T
9
8
7
6
5
4
3
2
A
K
Q
J
T
9
8
7
6
5
4
3
2

Study and learn this chart, and you won't be the user who recently folded K5o, or the user who called with 99. These are costly mistakes and there is no reason to make mistakes so soon out of the gate, before you've even seen a flop.

On that note, I hope you enjoyed reading. Look for more posts like this one in the near future.