Unless you are playing stud poker, you don't know what you opponent(s) have in their hands. Your decision has to be based solely on what is n your own hand.
The first part of this statement is true. The second part isn't.
Your decision is based on a multitude of factors other than what is in your hand. They include..
- Where you are sitting in relation to your opponent (if you bet after them, you have an advantage).
- How you opponent has been playing. If they play every hand you will play lots of hands against them. If they haven't played a hand in the past hour and come in with a bet now... you are probably right to duck out for a hand.
- Whether you are playing a tournament or a cash game.
- How many chips you have in your stack.
- How many chips your opponent has in her stack.
- In a tournament, how many people win money.
- How you have been playing previous hands (if you have been raising a lot recently you know that people are more likely to call if you raise again).
- Is your opponent in a situation where she is scared to lose (i.e. on the bubble).
And there are many more things to consider. What you have in your hand is only one consideration out of many.