So I'm not a part of this world at all and I'm super fascinated by this perspective. I hear your point entirely. How do you counter the issue with pre-structured interviews where the questions get distributed and you end up with candidates who learn how to answer your exact question (but lack the skills to actually be dynamic in their job, or even do their job)?
I used to interview for a big company, and I could tell some candidates already knew the questions, but I'm a bad interviewer myself as I tend to rate most candidates as 7+/10, I very rarely found coding-illiterate candidates.
When I detected the candidate knew the questions, I'd switch order, introduce new questions I didn't usually ask.
The interview we did was quite extensive on the java basics and if the candidate somehow managed to learn all that stuff by knowing the questions, that was a pretty good sign anyway.
It was just this one time I found a candidate who aced every question I asked, even OOP, Design Patterns, I made up on the spot a code-design challenge, the guy suddenly was not so brilliant, but still managed to hold his own and I didn't penalize him for my impression that he knew the questions, he was way better than the usual candidate anyway.
Perhaps the stakes were not so high as in the USA, but I can say I've never found someone who would have failed without knowing the questions in advance; I did fail people who were trying to cheat on the phone interview, but those were rare cases.
My impression is technical interviews just filter programming-illiterate programmers and people who don't give a f#ck -- as a general rule.
There's also the 30% of cases where the interview is made up to show the candidate he's not really all that senior as he thinks and to lowball his salary request.
And some companies have very high technical interview standards because of some cultural inferiority complex (we are just like Google, you see...).
If I could answer that question, I would be a billionaire already.
Programming interviews are almost exactly akin to actor's auditions. Just because you flunk an audition doesn't mean that you're a bad actor. Also, auditioning takes a special skill and it's not very much like being a real actor. But they still do it to this day. Programming interviews are similar.
The best hiring model I can come up with is the Netflix model. Pay top of the market, hire and fire people quickly if they don't meet expectations, with a generous severance. Have high expectations, reward the ones that can fulfill those expectations, and quickly get rid of those that don't. It's ruthless, but the Netflix engineers I know love working there.
