Because if you do a solid good job that's a 2, but a couple 2s fairly quickly gets you on the RIF train to getting fired. Which is nuts. So everyone has to outcompete their team trying to get those 3s. And the manager is put in the nasty position of having to rotate the 2s (which they must hand out since there's always quotas) among the team so that hopefully nobody gets RIFd while still meeting the quotas.
(Assuming a 5 point scale here, which is fairly common, but I've seen other scales but the same principles apply.)
My partner was a manager at the G of faang for many years and twice a year the whole month was blocked off for 60-80 hour weeks just to fill endless review paperwork. And their employees spend all of the six months between reviews scheming ways to fill that next round of paperwork. It's all a monumental waste of time, effort and cause of unnecessary stress for everyone.
None of this nonsense exists in other industries, at least as far as I know from talking about it with my circle of connections in other professions such as law, medicine, accounting.
