I would slightly amend that to say that a successful manager manages results, not people. A leader is responsible for making sure standards and deadlines are met. S/he accomplishes this by ensuring communication is happening, progress is occurring at an acceptable pace, and obstacles/conflicts are dealt with. Otherwise, the individual or group should be left to accomplish things as they see fit.
The best leaders I have had have also been "coaches" people that see my strengths and leave them be but find an area where I can improve and help me do so. I have been fortunate to have several leaders like this during my career.
Yeah, me too. I once had a leader call a multi-thousand-dollar error on my part "an educational investment." He then explained to me what I should've done differently and I never heard anything else about it. It was awesome because A) I knew how to avoid that mistake in the future (and I guarantee you I never made that mistake again) and B) I felt a lot more confident in my job and my leadership, and confidence plus security kind of naturally results in better work overall. It was a great way to handle it.