I'm gonna play devil's advocate even though I agree with your point. Firing people sucks. As a manager, it's a terrible feeling to tell someone they are out of

I'm gonna play devil's advocate even though I agree with your point. Firing people sucks. As a manager, it's a terrible feeling to tell someone they are out of a job. Not only that, but often times my own pay might be tied to how many people I manage, so in some cases, it's better for me to have people around doing nothing than to let them go. By having a forced ranking/culling, you somewhat alleviate the tendency of people not wanting to fire non-performing staff. Companies should have a culture where this isn't the case. It should be encouraged to let people go with nice severance. You should be judged on your teams' output, not on how many people you manage. You should be rewarded for doing more with fewer staff. But enforcing this is very hard in a big company while enforcing a 6% cull is easy, so that's what happens.