When performance is a concern, the manager raises it directly with the teammate within a week of identifying it. We are explicit about what's not working and what good looks like.
We try to support a turnaround. We are also honest with ourselves when a turnaround isn't going to happen, and we move with care rather than with delay.
We do not stack-rank, do not have a quota for letting people go, and do not use performance management as a budget tool.
