Big Mouth: State the obvious, loud, either talk too fast or too slow, and migraines usually begin to transpire around them.
So what about in a story where no one can hear them? No one can you hear you scream in space right? Or the woods? Well what happens on the page? Occasionally too much. Yes, dialog is vitally important; that's not what the point is.
Take this for example:
"Hey Tony, where are you going?" Helen asked.
"Then why do you have your shoes on?" she asked again.
She said, he said, she asked, he asked. It's often redundant after one use. We all know that this symbol right here (?) means a question has been asked. It's also cause for sloppy dialog. There has to be a mix of actions and speech in the same little section.
No one cares if Tony was picking his nose. Helen may ask why somewhere in the dialog anyway. Or if someone is doing jumping jacks. The reader will understand that. Contrary to popular belief, some humans actually have brains.
Now whether or not they have to actually search for it is up to them.