Wit lets everyone let go of the breath they are holding in.
PS: In a way that does not target anyone in a mean way. Wit is not mean. It's clever and does not rely on timing or a target to take the fall: It's self-sustaining humor.
It's like a breeze in a stagnant room. Without the right conditions, it's harder to be witty - it's still possible though. It's like brevity: a finely tuned art of words.