As a manager I believe it is my duty to coach my direct reports so that they can succeed in their career. Sometimes that is not possible in their current position.
I have a direct report whose career would be better served elsewhere. There just isn't an advancement path here for him; and one won't open up for two or more years. He knows this and complains about it enough that he has become somewhat toxic to the team and the company. (Toxic enough that he could be terminated some day.)
Moving to a new company would be good for him. I admit: it would be good for me and our employer too.
If we were a larger company and he could succeed better on another team, I'd have no problem coaching him towards moving to that other team. However, we are a small company without a large selection of teams to move to. His only option is out and he doesn't realize it.
I think his career goals would be best met elsewhere.
Can I tell him this (is it legal)? Should I tell him this (is it ethical)? How could I tell him (e.g. hint, be direct, ask someone else to hint to him)?