What I've most definitely learned through my degree, work life, and the work life of others, is that it's not so much about actual competency, but perceived competency. I.e., those who believe they are highly competent, who think they are more skilled than others, behave more confidently, put themselves out there more. They act like they are competent, and people believe them. By the time they are discovered to not be quite as competent as they were initially believed to be, they've had their promotions and are secured in nice, long term contracts.
I've seen this so many times. And I've heard more or less directly from a man who was mental health commissioner for a leading mental health charity. He outright said that if you are willing to do some major arse licking, you'll get very far, and that's what got him to his position.