It is one of the most powerfully destructive forces in the world. It can drain motivation, destroy creativity and undermine success. Yet it happens often and many times we don't even realize it because it is sometimes subtle. Suggesting an alternative to a decision or selection someone has made can be interpreted as criticism. So can a snicker, a sarcastic remark or inattention.
People become overly sensitive when they have had a history of being criticized.
The criticism may not have even come from the same person that it had come from in the past. But once someone has reached saturation, the next incident can be the last straw. Sometimes we speak of constructive criticism. It sounds better, and while it is intended to help the person who is being criticized, if handled poorly, the impact can be devastating. Criticism puts us in the role of adult and child.