Leaders who truly know how to deal with people,
Gather feedback not only from the top down but also from the bottom up, Gathering feedback from the team on how things are going with the leader,
Some teams make theater play surround the PIP as if the employee were a kindergarten child, even hypocritically pointing out flaws and feedback that didn't exist to justify a future termination. This happened to me, and a member of HR witnessed it all..