Maybe this example will make it clear to you:

HU game. You and your opponent have $100 stacks each and you know that he likes raising to $99 dollars on the first hand for some reason if you just call in the SB. You have pocket aces. You just call and he raises to $99, you raise him all in. He calls his last dollar. He was clearly getting the correct odds to call and hero would prefer him to fold (aces is at best a 80% something favourite) but this does not mean hero made a mistake.