We spend so much time screening engineers, going through code tests, assessments, live code interviews, whiteboard interviews, system design interviews etc.
Yet, we don't have the same vetting standards for managers, at least from what I've seen. There is no "Cracking The Engineering Manager Interview" book, for example. The gauntlet isn't there the same way. There also seems to be far more hesitation to look at management as an issue for negative outcomes vs how its ascribed to engineers[0] much more quickly, yet a manager can make or break an entire team - even turning good engineers into bad ones.
While I suspect that management looks out for management on this, you'd think a broader trend among the community would raise awareness around this, but many well meaning engineers continue to look only at their peers, unless management is particularly ineffective or egregious, rather than evaluating possible management and team practices
[0]: which is the reason given for why engineers have these arduous interviewing requirements, to weed out any possible "under-performers"
Pretty rare to get an honest feel for upper management when interviewing or assessing a potential employer. It's only once you're inside, and usually after a few months (sometimes longer) that you get a true feel.
But the weed-common presence of conservative management is what makes disruption possible.
Swings and roundabouts.