Silence As A Response

Why is it that silence is seen as a bad or wrong response to something?  I sometimes hear a person say, "I could not think of anything to say."  Maybe not thinking of something to say is a grace.  You were not supposed to say anything.  Your presence, maybe a touch, a caring look was enough.  Someone told me that if your words cannot improve on the silence, then don't say anything.  I try to keep my blogs somewhat short...not too many words.  Friends of my sister Maureen wish that I would say zero words and go away to a monastery to repent.  Well, I am at a monastery, repenting, but we have internet!