It's usually triggered by an experience of hurt or anger where a person allows these feelings to fester rather than dealing with them directly. When people become cynical of one thing, it can slowly turn their attitude against everything.

What causes a person to become cynical?

Cynicism is part of a defensive posture we take to protect ourselves. It's typically triggered when we feel hurt by or angry at something, and instead of dealing with those emotions directly, we allow them to fester and skew our outlook.

What is a cynical person like?

distrusting or disparaging the motives of others; like or characteristic of a cynic. showing contempt for accepted standards of honesty or morality by one's actions, especially by actions that exploit the scruples of others. bitterly or sneeringly distrustful, contemptuous, or pessimistic.