Setting chimes for a door sensors can be useful when your home alone, and like to be aware of your surroundings.
I’ve set this up so our keypads will chime when any of any of our doors open. I’ve notice the usefulness of this when my in-law came over and open our garage door when I wasn’t aware they were coming to our house. Apparently they told my wife and at least I wasn’t too surprised when I meet them out side.
To do this you need to configure two things.
1) On the Device section you need to click on the “manage” button on the contact sensor which you like to enable to make a chime.