Many people tend to have huge egos, and that is fact. Evolution wise, males are competitive against each other for the purposes of procreation with females. The fittest males attract the most females. In biology standards, one can say the purpose of life is to procreate and pass on genetics for successive generations.
One can often see the result of this in any commercial gym. Many people will forego technique, range of motion, and form in order to appear to lift more weight and inflate their egos. They will brag about how they can lift this much weight, when most of it is done with tiny range of motion. Not only is this unimpressive, but can also be incredibly dangerous.