Good managers, as you've described them, are glorified babysitters.
It doesn't matter how well they follow policy, how fair they are, or how equally they treat the employees if they aren't doing so en route to attaining meaningful goals for their workgroup/station. Some people see an objective and their minds start considering the options to achieve it. Others see an objective and their minds start considering the reasons why they probably won't achieve it. It's just a difference in the way people are wired.
The effective managers and the ineffective ones both work in the same system.