There is no sense in doing a lot of barking if you have nothing to say. (Snoopy in the “Peanuts” cartoon.)
A barking dog can be either an important warning or a continual annoyance. The same can be said about human beings and their speaking. Sometimes when we are besieged with an overactive talker, we might want to say, “While you’re talking, why don’t you say something.” That would be impolite, of course, so guard your words carefully.