Let me add my experience. I've never had the FKANG experience but for a number of startups that I've contracted for I've had a chance to observe if not participate in the hiring process.
They were US startups and they've all tried to emulate what I think of as the FAANK process: so you have an initial call, a technical screen a couple of other rounds of technical screens, that maybe include system design, and fit/behavioral with people you might be working with. In practice the people who got hired endured 5 to 7 interviews.
It's interesting to see the statements here saying that the reason for the large number of interviews is to assess the candidate from a number of dimensions and perspectives. What I observed was that was not how it really worked.
My position as an outside contractor, as well as someone who loves chatting with people, made me sort of the ideal confessional for the engineers who directly participated in the hiring process.
The main dynamic that drives having such a high number of interviews is that the hiring process is less about assessing the candidate (beyond a certain point) and more about allowing to play out the implicit political power and conflicts of the people who are judging the candidate.
For example in the first startup we had this engineer who was identified by the CTO and co-founder (who formally stepped down as CEO) as being a good potential hire, and they excelled in the technical aspects of the interview but they received meh votes from one of the engineers who was lead on a significant project and had a bit of clout, at 3rd interview, and were subsequently rejected, after 7th interview.
So basically the feeling of the staff that I talked to was the reason there existed four more interviews after the consensus was to hire, was to allow the political player to promulgate their preferences and manufacture consent with the motion to reject. So through a careful orchestration of four additional interviews closely managed by the political player who asked doubt-casting questions in each debrief this lead was able to cultivate doubt where formally there had been consensus (besides his sole dissent -- he wouldn't have been working with a person anyway, heh :)). So basically it would have been intolerable for this politically clouted lead person to have "lost" to those other staff with less clout by having their preference denied. I felt really sorry for the candidate but I heard that when they got the 7th interview rejection that already accepted an offer at a FAANG, go figure. Heh :)
Observed a similar dynamic play out in another hiring process at a different startup. That stage we had the director of engineering identify candidate that was a good hire. And basically softly railroad them through the process which didn't prove difficult as everyone was mostly on board and the team was really desperate for high quality technical talent with the right skills and this person had that.
So what was interesting to observe was that the other candidates in the pipeline at that time were still taken through interviews even though this person was basically from the initial screen stage already being moved to be hired internally, and all of the other interviews were basically friendly get to know you sessions with super lightweight technical questions and a lot of I suppose you could call it confirmation bias but it's really just you know people being nice to someone they want to work with.
But all of these other poor candidates in the pipeline were still put through all these interviews with the idea that you know there was still a role out there for them being told the same things they would have been told were they you know actually under contention. Or maybe that was because we didn't know if the candidate was going to accept or not but they seemed pretty keen and the thing is I'm almost 100% sure the team wouldn't have hired any of the other candidates in the pipeline anyway.
But again I observe the dynamic where the debrief interviews about these non-starter candidates were basically role-playing games for politics in the organization where people projected their preferences into little power games against their colleagues to try to have their own preferences be the ones that win. Decidedly wasn't about those candidates at all because they had not even had any chance of being in the process. The only point of the subsequent interviews of all those non-starter candidates was to act as an arena for the staff to role play their sort of political status conflict games with each other but this was never exposed or stated it was just this sort of implicit thing.
So given that experience I wonder how much that is a dynamic driving these lengthy and in a lot of cases unnecessary interview processes across all of the tech hiring and organizations that are utilizing this type of process these days.
I don't think it could apply everywhere I think there's probably places like Amazon where they are really doing something different. And like I said I don't have any of the data from the ZFAMG stuff.
But I'm reminded of something Peter thiel said which is you know in academia the battles are so fierce because the stakes are so small. But another side of that is everything so secure there and that's why the stakes are so small. Same thing is true in tech I mean once you score one of those 150k plus contracts and you're doing something that you basically love doing it is a great ride and everything really is so secure so how do people take out their natural ape brain competitive urges in that environment? I think as another commenter said, where can people project their risk-focused paranoia in such a low risk environment? and it's onto personnel.
So I think there's definitely the case to be made for maladaptive pathological psychological underpinning of these lengthy hiring processes as much as there is a case to be made for how they could be useful at getting data from from a bunch of candidates.
Personally I think the best types of hiring interviews are some sort of pair programming work emulation. The problem with that is in my experience companies are generally very terrified to open up their internal code base to the eyes of outsiders because they're basically scared that oh my God people are going to steal our code.
But it's always the case where after someone's hired and you start working with them that's something you end up doing and that's where you really get a sense you know if can I trust this person to deliver and do they match what people are being saying about them from the interviews.
So I just think those sort of work emulation tasks you where you're pair programming or talking through something with someone it really has more of a place than it seems to have been given so far in most of the places that I've seen and heard about.