“Why bet so much?” This is one of the most common questions I hear at the poker table (at high-stakes games, anyway). But like most of the information we get, this line of thinking seems to lead to losses as often as it leads to good play.
The idea seems to be that a large bet requires some explanation, or that some bets are “normal” or “standard” and don’t count for much, while others that are large or small contain more information about the opponent’s hand than “normal” bets.
However, different players interpret these patterns differently. Some people tend to assume that big bets usually mean bluffs, but I have seen these types of bets made for value at times when, logically, a value bet would be better. Other players assume that big bets always mean strong hands.
To be honest, there is no absolute truth when it comes to what bet sizes reveal. Many players actually restrict themselves to betting within a few pot-sized limits, usually 50 to 80%, and only deviate from these limits for very specific reasons. If you can determine these reasons, you can determine the strength of your opponents’ hands with a high level of accuracy.
However, there are many situations where very large or very small bets do not mean anything in particular. They can easily be made with a balanced range, in a way that does not do anything negative for the player compared to other bet sizes he could employ. Learning to distinguish between situations where large bets can be balanced and situations where they cannot is key to determining whether your opponent is revealing something in particular by betting this amount over another.
Higher bets usually come from a more polarized range
The most important thing to recognize is that big bets generally require a more polarized range. Intuitively, this makes sense. If you make a bet that is small relative to the pot, the odds will make your opponent call even with relatively weak hands, which means you don't need a strong hand to be ahead of his calling range. If you bet more than the pot, then your opponent has to call just as often, and when he does call, it's because he has a strong hand. Consequently, you can make this bet for value with very strong hands or as a bluff with weak hands, but you can't extract value with average hands.
What causes the most confusion here is when people assume that polarized ranges are necessarily weak. It's much easier to make a weak hand than a strong hand, logic says, so if you can tell whether I have one or the other, shouldn't you expect me to have the former much more often than the latter?
Not necessarily, for two reasons. The first is that even if I have more weak hands that can be made, I can check them whenever I want. I can get to the river with 80% of the bad cards or with 3% of the monsters and still make a balanced overbet by checking most of the bad hands.
It's not hard to construct a scenario where you would rather fold good bluff-catching hands to this bet. Suppose an obviously recreational player has barely played a pot or two in the last few hours. After checking the big blind and checking twice on a :Kd :7c :7h :5s board, he suddenly goes all-in for several times the pot on a river that shows :2c . He never had a chance to fold his bad hand, so he has a good opportunity to improve his hand, and now he can make a balanced bet, or an unbalanced bet if he thinks he's facing a bluff. Here, I would fold hands like 76 without hesitation to this all-in.
It is worth remembering that it is not always easy to have weak hands.
The second problem with this logic is that it's not always easy to have weak hands. Suppose a player has called a big bet on a :Ad :9d :6s :2h board. The river comes :Td , and now he's overbetting. Even if you conclude that he's either bluffing or value betting with an excellent hand, you can easily fold a set. By calling big bets on the flop and turn, this player is telling you that he either has a high showdown value or a very good draw. On the river, basically all draws can complete there, and the other hands he might be holding probably have too much showdown value to turn into a bluff. So he'll have a straight or a flush too often for you to call purely with a bluff-catching hand.
Players who can’t fold a set will often tell themselves that their opponent could have AK or A9, so it might be worth going into more detail about why you shouldn’t expect to see these types of hands at high stakes like this. They are undoubtedly strong hands, perhaps strong enough to value bet in many situations. Here, however, your opponent has so many strong hands and so few bluffs in his range that you have no incentive to call an overbet with hands that would lose to A9. After all, we’re talking about how folding a hand can be advantageous.
This brings us to another potential objection: could your opponent be turning AK into a bluff? It’s possible, but it’s unlikely that this would be an advantageous play for him. And if it is, there are probably better ways for you to take advantage of it.
To make your opponent indifferent to your bluff, you need to call or raise often enough that the EV of your bluff is the same as the EV of your checking. When your opponent is holding a hand that has no showdown value, the EV of your checking is 0, so you should call often enough to equal the size of your bet divided by the size of the pot so that the EV of your bluff is also 0.
However, if the EV of checking is greater than 0, which is probably true in this case, then you shouldn't call very often. If you call often enough to make the AK bluff have an EV of 0, then you are being exploited by an opponent who checks, since that play gives you a higher EV than bluffing.
But let's say your opponent makes a mistake and bluffs with AK, even though checking is a better play against your range. If you knew he had AK in his betting range, does that mean you should call with your set?
But, after all, is it worth trying to catch a bluff in this scenario?
Again, not necessarily. The mere possibility of bluffing is not enough to guarantee a bluff-catching hand will win. You have to consider whether there are enough bluffs to compensate you for the many strong hands he could be holding.
If your opponent is really turning a lot of strong hands into bluffs after you check the river, then while it is correct to call with your set, you should consider other adaptations. This player is probably encouraging you to check all of your strong hands on the river. Instead of betting half the pot when you have the flush and praying for someone with top pair to call, you should check and let him overbet with your measly top pair.
Of course, this requires planning a strategy that is in line with your information about your opponent, and how he can usually play wrong before he acts on the river. The reason I’m always suspicious of arguments like “Maybe he’s turning AK into a bluff!” is that they fall into the logic of the post, i.e. “after this, therefore caused by this.” It’s one thing to say, “If I check this set, he’ll overbet with AK and I can call.” It’s another thing to check, get overbetted, and then decide that he has AK. This last example sounds a lot like you’re looking for an excuse to make what is fundamentally a call based solely on curiosity and frustration.
The above examples are cases where it is difficult or impossible to balance an overbet profitably. Either the player does not have enough bluffs available or he has more profitable options with the hand than just using it as a bluff.
In other situations, however, an overbet need not necessarily be interpreted as a strong or a weak hand. Suppose the button, who was the preflop aggressor, bets on the flop and river, against a player who called preflop from the BB. The board shows :Ad :Kh :5c :9c , and he shoves all in on the river :2d .
In this case, both players' ranges are probably wide enough to make it comfortable for the button to overbet even with a good hand like two pair for value. This is because, since he raised from the button, he also has a lot of bluffs available, which means the big blind can't trivially fold a hand like AT to a river shove. This is particularly true when the big blind has little to no AA, KK, or AK in his preflop calling range.
Conclusion
Of course, against a particular player, you may well be able to call or fold in order to exploit your opponent. However, unlike the previous examples, here there is not necessarily a situation where you have an advantage. You may just be indifferent or almost indifferent with the majority of your range. This is the kind of situation that excellent players can take full advantage of, and like a bad beat preflop, there is nothing you can do except shrug your shoulders and accept it.
Sometimes the answer to the question “Why bet so much?” is simple, “Because this is a favorable situation to overbet with a balanced range.”
Article translated and adapted from the original: Why so Much?
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