Profit needs to come from many different sources. If you only rely on somebody getting a big hand against your bigger hand, then you will not be profitable in this game. Those situations don't arise all that often. Granted, you still want to take advantage of those situation. In order to be profitable, you must make better decisions than your opponents regardless of the situation. This only happens if you have a solid understanding of the basic concepts: starting hand ranges, aggression, appropriate bet sizing, etc. The goal is always to maximum your gains and minimize your losses.