There is an old philosophical question, centuries old in fact in different variants: "If a tree falls in a forest and no one is around to hear it, does it make a sound?" Does silence make a sound? Can silence be useful? One can argue that silence makes it own unique type of sound that has meaning and value.
Perhaps the hardest thing we had to learn and control when we started teaching was air time. It is so easy to talk, talk, talk, and talk. Lots of points on slides, read them all, give lots of points, give lots of slides. We started that way. Over time, we learned that the amount of content, content per slide, and the proper pacing and speed is important. You should not out-pace or overload the students with content, but those are other topics. This one is about silence and pauses.