When you are making a bet (or raise), you should always ask yourself “what is my bet trying to accomplish”. It should be one of these:
- Increase the size of the pot because you expect to win pot at showdown (or in future streets).
- Get the opponent to fold because you expect to have worse hand at showdown.
- A mixture of #1 and #2 (Semi-Bluff)
- There is a 4th reason that I do not want to list here because it often cost more money than it saves against strong players, but can feel “comfortable”.
When you make a bet you never want all the worst hands to fold and all the better hands to call. But often I see players on the river make a bet with the type of hand that will only get called by better hands and will cause all worse hands to fold. That is a horrible outcome. You are risking money (better hands calling) with almost no chance of making money (because worst hands fold). There are times when your hand is too weak to bet (better hands will call) but too strong to bluff (worst hands will fold). The size of the bet also plays into this factor, but one must be careful on how they size their bet, because that can reveal too much information to your opponent (if you always bet a lot with strong hands, and little with weaker hands opponents will use this information against you.)
You need to make sure that when you are betting that either (1) weaker hands will call and your bet will make money -OR- (2) worst hands will fold and your bet will make money. If you have a low pair (or even Ace-High) on the river you are sometimes in the situation where stronger pairs will call your bet, but weaker pairs will fold to your bet. In those situations you often do not want to bet; you should check-fold or check-call depending on the situation.
The mixture of (1) and (2) should be only made when you have ways to improve your hand to the better hand, but currently almost certainly have the worst hand. When you make a bet in this situation (called a semi-bluff) you do not mind so much if your opponent folds a better hand (you make money) or they if they call because then you can still win by hitting your draw OR bluffing on later streets.
The 4th reason is making a “defensive” bet when out-of-position. Occasionally, against a specific type of player, you can make a “defensive” bet on the river when you are out-of-position. I am not a fan of defensive bets because they can be easily exploited by tough players, and I think they can be over-used. “Defensive bets” are smallish bets on the river that set the price for your weak/scared hand, and are mostly used to try and prevent big river bets by your opponent when you check to them and you have a weak hand they could be best. You really only want to use “defensive bets” against opponents who have a good balance of big bet bluffing the river and making big bets with medium to strong hands. If you are against a player who bluffs too often, you should be check-calling the river instead of using a “defensive bet”. If you are against a player who doesn’t bluff enough with their big hands, who should be check folding. It is only against players who have a good balance between bluffing with hands you can beat but also making big bets with hands that beat you that you should consider a “defensive bet”. And even then, you don’t want to make a defensive bet against a tough player who is capable of re-raise bluffing on the river, totally defeating your “defensive bet” by making the decision even tougher.