1. Dont reference an employees salary in front of other staff.
This is private and confidential information, not public. Whether the boss is saying, I dont pay you enough, or I pay you too much, this type of comment will lead to resentment among staff members. Broadcasting employee earnings undermines their position with the rest of the staff. Theyll either think the employee is willing to work for peanuts, ruining their chances of earning more, or that theyre overpaid.