Sometimes a user might incorrectly edit a question, in an attempt to reply or answer or whatever. Is it possible to reply to the suggested edit to explain why their edit might be wrong?
The user can see if their edit was rejected or approved, and can see the reasons given by the people who did the reviews. If you have old reviews of your own, you can do this as well, whether or not you have edit privileges. You can list your reason for rejection and the user will see that if they review their edit.
Also see this M.SE post