I'm not a manager (yet).
However, I do have a question about the coaching model. It seems to me that the coaching model hopes to improve the productivity of a direct report before his/her job is in jeopardy.
I whole-heartily embrace this idea. I have seen many cases where people who were under-performing were basically just isolated. (I've worked for big corporations for all of my career).
However, at my company, there is basically a quota for reviews. 10% of the population [i]has[/i] to get binned as needing improvement. (This bottom 10% gets punished financially.)
So, basically we have a situation where my manager has to give someone this bad review, and has no control over their compensation after this review is given.
In this case, what is the point of coaching someone? Even if that employee does get better, someone in the group is going to have to get a bad review? Can the team as a whole ever get better in this environment?