I wonder if this calculation ignores a bit the effects of "meta knowledge". I.e., many of the "new" people may be new to this particular process, but may already have expert skills in the general domain of buerocratic processes - and therefore may be able to adapt much more quickly than a "real" newbie, i.e. a person that works in s buerocracy for the first time.

I imagine this similar to how software developers may be new to a particular project or codebase but may still bring with them general domain knowledge which lets them understand the project requirements or the intricacies of the codebase relatively quickly.