You missed the greatest point in my opinion, passion and love for the work being done.
It is the irrational thing that drives people. If you lack passion for the job you will do it poorly, no mater what is your education or skill set.
A must have is a sense of self-accomplishment or you will be a drone expecting month to month paycheck doing in best case, mediocre.
Unfortunately (in my opinion), tendency in IT is to fine grain till all it is left is powder
... causing a job to be done by more people then are required for it.
This is limiting and bounding to the people inside the process, making them drones.