If you win every time you have the best hand, you're calling too much.

Ideally, you'd like to call whenever you had the best hand and fold whenever you don't. Unfortunately in most cases you don't know for sure whether you have the best hand, the best you can do is estimate the chances and call when you're more likely to be ahead, and fold when you're less likely to.

On one extreme, if you call every time, you're never going to fold the best hand, but you're going to be paying off a better hand a lot. On the other end, if you fold every time, you're never paying someone off, but you're often folding the best hand.

The most profitable action is a compromise, where you'll call if you think you're X% likely to win (X determined by pot odds). This means you're sometimes paying off a better hand, and you're sometimes folding the best hand, neither are necessarily mistakes.

If getting bluffed was never correct, bluffing wouldn't ever be correct at high levels, but it is, and winning high-card hands are the most susceptible to it.