People join companies (come to work on the promised scope and tasks) but leave managers.
That’s a popular quote which in my life was more often true than not. As any simplification there are always the cases when it’s not true.
One case, some can argue, is when a direct report deserves a promotion (according to a direct manager), but the manager is not able to provide such an outcome regardless the attempts.
In such a case, if the direct report is so demotivated by that fact that decides to leave the company, who is he leaving: a direct manager, managers above, decision making culture (to which each of the managers contribute)? Is the manager good in this case? Who is a good manager?