The Low Probability of Hiring Software Engineers
A fairly complicated description of hiring, and although somewhat obvious, more easily described by a simple probability equation. So, excluding the likelihood of getting past the recruiter:
P(hire) = P(phone screen) * P(sample project) * P(2 interview teams) * P(accepting)
Even including some kind of Bayesian inference, increasing odds for passing subsequent steps, or tilting candidate characteristics, it still leaves the probability of a hire fairly low, and an increased likelihood of a rejecting a good candidate, a false negative, but one can understand the aversion to a false positive, as it can be very expensive.
Source: Bayesian Inference for Hiring Engineers