Could easily be against your boss's best interests, or at least what your boss thinks is their best interests, in a large company, too. That's the hole I'm currently trying to fight out from.
I don't see how it's in a manager's interest to not promote good work that their team members are doing. If your manager says to his/her superiors things like, "look at the talent that's thriving under my leadership", that's a good thing for everyone.
Examples that come to my mind, would be the risk that the employee gets promoted over the boss, or alternately, that the employee is poached and shifted out of the group by a different group boss.
