The pause is an important part of any dramatic action. We use it for two reasons. One is to pause before a dramatic moment in order to build audience suspense for what will come next. The other is to pause after a dramatic event to give the audience time to absorb, reflect and internalize what has just happened.  This refers to events, but can also be a phrase, a line, or even a dramatic word. If you listen to comedians, there will almost always be a quick pause just before the punch line, which raises audience tension for a moment and then brings them down with the punch line. That makes it funnier. You do not have to make a big deal of it. It doesn't rise to the level of filling pages of rhetoric about it. Just find the most important moments in a scene or line and decide whether you want to build tension before it or allow its impact to go deeper after it. In all of our workshop scene work, we expect scene partners and monologues to have at least one important pause.  The timing is variable. A short pause builds a little tension. A long pause builds a lot of tension. But if it's too long you lose or confuse the audience. A 1-2 count is probably all you need unless it's like the most important event or moment in the play and then you may only have a 4-5 count.
Try it, with different moments and different times. Try it both before and after to feel the effect.