In the chapter of his interview in Coders at Work[0], Norvig found that the strongest correlate in the interview process with success at Google was paradoxically to have been given the lowest possible score by one of the interviewers. He surmised that this was because in order for such a person to have even gotten hired at the end of the process, someone trustworthy must have seen so much potential in the prospective hire that he strongly advocated for the person to be offered a position which worked in spite of that other low rating.
Kind of ironic for a company whose product values are so tightly tied to quantitive data.
A qualitative assessment of that factor is hard because Google doesn't hire the people that it doesn't hire.
Another assessment could be that a divergence of opinion among interviewers is itself a positive sign -- programmers with strong controversial opinions who are willing to hold to them even in an interview setting might be better programmers for that.
A less sanguine assessment is that "success at Google" correlates with people who generate controversy around themselves, simply because that is something that creates visibility.
More recently, people who have and are willing to analyze data across many interviewees and interviewers at multiple companies (so they can see ongoing performance of a candidate a company passed on!) have pointed out:
After looking at thousands of interviews on the platform, we’ve discovered something alarming: interviewee performance from interview to interview varied quite a bit, even for people with a high average performance ... roughly 25% of interviewees are consistent in their performance, but the rest are all over the place. And over a third of people with a high mean (>=3) technical performance bombed at least one interview.
This isn't surprising - in fact, it would be surprising if it wasn't the case. This fact says nothing about the ability of Google's hiring bar to distinguish between good and bad hires, except that it is not a perfect signal.
Totally agree. It just serves as a useful reminder though not to fall prey to the fallacy of deliberately chasing the correlational measure as a matter of policy.
Kind of ironic for a company whose product values are so tightly tied to quantitive data.
[0]http://www.apress.com/us/book/9781430219484