My theory: most hiring absolutely doesn't matter (from the interviewer's side). Most people will either have the skills needed or the capability to learn said

My theory: most hiring absolutely doesn't matter (from the interviewer's side). Most people will either have the skills needed or the capability to learn said skills. Weeding out obvious poor cases is easy, the remainder is semi-arbitrary weeding out of true positives in hopes of weeding potential false positives. Much of higher education alone does a good job at pushing people to learn difficult things in a short timeframe, with little incentive beyond "getting that paper". Also, hiring is a lot like parenting, but the bad aspects magnified at least a few times. As you say, barely anyone knows what to do. No one has experience. Almost everyone claims to be an expert (not verbally, but they do act like it). Non-obvious bad choices often go undiscovered; as above, most picks themselves aren't bad (they just aren't great), or something else is blamed instead. Pride, neuroticism and personal bias play huge parts in the decisions. Worst of all, no one actually reads the studies showcasing most of what hiring managers do have close to zero correlation to anything. I'm really just waiting for a mass study where two companies do an initial vetting, then company A throws darts at a dartboard and company B does the whole job interview shtick, and compare the results 2 years down the line. And maybe add a company C which actually does what studies suggest.