Top grading stack ranks are devised by managers who fundamentally believes people are fungible widgets, and like a widget, have a defect rate that’s statistically analytic. I’ve rarely found an engineer I’ve hired that is worth letting go. Sometimes engineers come in and struggle at what they are assigned, but as a manager if I take the time to understand the person, rather than discarding the widget, I’ll find what they are good at and I can find a way to make them do that. There was always “something there” when we hired them, and it was my fault if I didn’t match them to the right work, style of working, or environment for working.
The managers of widgets are sad widgets. To be a person as a manager, you have to manage people.