Then those managers are bad at their jobs and should be PIP-ed even more ruthlessly.
It's always interesting to me how managers get a complete and utterly unexamined pass in these conversations. The bar is so, so low for them. Managerial incompetence can be breezily cited as the reason for a horrible policy, like managing out a fixed percentage of every team, and everyone considers it a fait accompli. After all, what would be the alternative? Managers actually being held accountable for doing the most important part of their jobs?
ICs must be held nose to the grindstone every minute of every day... but ya can't do anything about bad management!