Why a particular person has a personality full of ego?

The answer is not very easy to find.

As per the words of great saints our behaviour is a result of our past deeds.

Ego is sure to come when one tries to rule others and dictate terms.

A humble and soft spoken person full of kind words and actions can only lead to a refined spiritual activity.

One can make his life for the good work or just let it waist in acts of useless pursuits.

But who has the time to know what is good or bad?