> That's what you get when you have fixed quotas for firing people, e.g. bottom 10%. After a few rounds you have some very good people left

That is not a general statement, bro. Not generally "very good people" are left, but people who are very good at achieving certain ratings. It can very well happen that for instance your top coders are actually in the bottom 10% because they don't know "how to human". People who only focus on social skills rarely end up in the bottom 10% tho. So this whole system depends on having very meritocratic rating systems or you end up actually increasing the speed of getting parasites in and normal people out.