There is no effectiveness without discipline, and there is no discipline without character. - Stephen Covey

In the words of Erich Fromm, an astute observer of the roots and fruits of the Personality Ethic: Today we come across an individual who behaves like an automaton, who does not know or understand himself, and the only person that he knows is the person that he is supposed to be, whose meaningless chatter has replaced communicative speech, whose synthetic smile has replaced genuine laughter, and whose sense of dull despair has taken the place of genuine pain. Two statements may be said concerning this individual. One is that he suffers from defects of spontaneity and individuality which may seem to be incurable. At the same time it may be said of him he does not differ essentially from the millions of the rest of us who walk upon this earth.

It comes from within.

Inevitably, anytime we are too vulnerable we feel the need to protect ourselves from further wounds. So we resort to sarcasm, cutting humor, criticism — anything that will keep from exposing the tenderness within. Each partner tends to wait on the initiative of the other for love, only to be disappointed but also confirmed as to the rightness of the accusations made.