We live in those times where self-esteem and belief in one's self have become a luxury. A luxury not everyone can afford. Why? In view of the fact that people have come to love degrading others. At one point in life, all of us said something to someone that had hurt their belief. And in turn, ended up affecting their self-respect or bring doubt in their own self.
The words that were once used as flower seeds in a garden for encouragement are now used like blades to cut down the other person's belief to the extent that they would crumble down without us knowing it. It's a common belief that only strong people are not scared of criticism but why do we forget that every person is strong in his own right. Yet everyone ends up breaking in their own way as well.
It's true that one can't make others believe in himself unless he believes in himself. But that belief in oneself is too expensive these days.