My last boss was my favorite manager, walked the fine-line between being fair but firm-handed, perfect balance between appeasing upper management and having his employees backs.
I tried to squeeze as much knowledge and information out of him, directly and indirectly.
One of the gems I gleaned from him was that 80% of good management is done during the hiring process. The interview process is *NOT* about assessing a person's skills at how well they will be able to do their job, but the kind of human being they are outside of the job.
Hire a trustworthy person and they will be easy to manage. Skills can be learned eventually.
You see it all the time, where a lot of smart people IQ-wise come with terrible personality traits: narcissistic, abrasive, poor social skills, and an overly-high self-opinion of their actual skills. These types of people are terrible to manage and create more of a drag on the organization than the person with lesser aptitude, but greater attitude.