Dialog is a tricky thing. I hold to the idea that every bit of dialog must push the story along in some way. It can be used to round out a character, or perhaps reveal some information the hero doesn’t know.
But be careful. Dialog, like everything else in fiction, must be believable. Your readers get to know your characters, so the dialog must sound like something a character would say. For example, if your character were a 15-year-old male, he likely would not say “I appreciate your comment, Ms. Smith, and will combine it with other feedback I’ve received.” That is, unless you have one incredibly smart and experienced 15-year-old!
And people don’t speak in complete sentences. You would never hear this:
“Good morning, Mrs. Smith. When I parked out by the curb this morning I noticed that someone has left a potted plant in the street. I fear the plant will shortly be dead if it does not receive abundant water.”
Perhaps it would be more like this:
“Some idiot dropped a pot on the road. I nearly hit it!”
Another possibility, taken from Broom 1, page 131:
“You’re on. Thursday morning at eleven.”
“Yes, whatever time zone you’re in.”
“Mountain time. Not Pacific time,” I emphasized.
“Right. See you then.”
Now that sounds more like real interaction. Both people are in character. Each says only enough to convey the required information. It’s terse, but not abrupt.
Read your dialog out loud. Does it sound natural? Would you ever say something like that to a friend? If it doesn’t sound right, it probably isn’t. As you interact with your friends and colleagues, take note of how real people approach conversation.