a time to manage

What is it about management that means that so many people find it difficult and/or avoid doing what they are being paid to do, especially in terms of people management? Can management be taught or is it instinctive, intuitive plus observation and experience of life?
Some techniques can be taught but i'm not convinced that attendance on courses makes a manager and the more courses attended doesn't make a better manager. I know of people in some wlaks of life who have been sent on 5/6 + courses regarding the same issue but they are no better at that issue at the end of that process. Sometimes we have to recognise that someone is in the wrong the job, may have been incorrectly promoted and do something about it, not keep postponing the decision and action.
Heyho! Sometimes i feel as though i have a sense, quite quickly as to whether someone has the ingredients to become a good manager, likewise the opposite.
The more we try to distil it into a rational / objective process the less convinced i am by the results. I think you can make limited improvements by training but not make a poor manager into a good one, excpet on rare occasions.