Good for making people re-read their Rand, but pretty terrible for maintaining stable systems. What if you fired the bottom 10% of law-abiding citizens, as in 'if you speed and get parking tickets and DUIs and beat your husband or wife, you get fired'? To what extent is 'made more money immediately for the company' a useful societal metric? Why do we benefit just because THAT company happened to make money? And yet that's the metric… better we should ask 'what did they do'. Money is essentially a meaningless metric.

If enough people decided 'the best people are those who bite other peoples' fingers off and keep them in a jar', that would be where the money was, and you'd be firing people who don't have human blood on their lips. There's no correlation between 'earning more money' and anything useful, societally or personally.

I think most firms that tried it have since scrapped it. It turns out to be about as effective as firing a random 10% and promoting another random 10% of staff.

Consider: a project is floundering. You put your best engineers on it to try and save it. It fails anyway. They get fired! Yay stack ranking.