Make a read and stick with it. Far too often, I see people go through each stage of a hand with the notion they will wait to see what their opponent does next and then re-evaluate. This is a fancy cover-up for two silly mistakes: being indecisive and getting attached to a hand.
Anybody who has played a lot of poker is familiar with this faulty pattern. I recently observed a perfect example of it in a live $5/10 no-limit hold 'em game.
Sitting in the four seat, a serious and competitive player had raised before the flop to $60, getting two callers who had initially just limped in. Holding pocket kings, he was already anticipating raking in a big pot.
The flop brought Jh 8c 7d, and both of his opponents checked. Still happy with his hand, he bet $150, a typical amount with $195 already in the pot. One player folded, and the other raised to $400.
As the player in the four seat began to analyze the situation, I had a good idea of what he was thinking. He was losing confidence in his hand. Many likely hands could beat his, and he never expected to be check-raised in the first place. He was hoping that somebody would call him the whole way and have a lower pair than his kings. This is when he became indecisive, feeling like he couldn't fold yet. I'm sure he considered that it would only cost $250 more to call, and that there was already $745 in the pot, giving him nearly 3:1 pot odds. Besides, he was in position, so he could see what happened on the next card.
At the same time, he was already attached to his two kings. He had not picked up any strong hands all night. It was frustrating. So, he began to rationalize his desire to continue. He no doubt thought about the possibility that if he folded a strong pair like this one, everyone at the table would start to bluff him relentlessly. Not to mention that he would appear scared of even a small amount of money, the paltry $250 being insignificant at these stakes.
Of course, he concluded that he could not fold. But he came to that decision not by sound reasoning, but rather by the attachment to his pair of kings that cursed him from the beginning.
Watching him, I could see that he never really made a read on his opponent. He got bogged down in coming up with excuses for not folding. When he finally decided to call and see what happened on the turn, which brought the 2c, his opponent went all in for a little over $1,000. After agonizing for a couple minutes, the player in the four seat said, "I just can't fold this hand," and called, losing to a set of sevens.
Always make a read even if it is hard to stomach, and make the right play even when it is difficult. Never let your emotions get the better of you. Success in poker comes mostly from patience and discipline.