I suspect the root of the problem is an unwillingness to take ownership for their action (or inaction). I've never been on a PIP. Even when I've given my employers reason to give me a verbal warning, their response has been: "that's not like you, don't let it happen again," and it hasn't happened again. I suspect that is true for most of those who have never been on a PIP.

Now I'm on the flip side, in a place where I may have to put someone on a PIP. What can be done has been done. There is only so much support and positive guidance that can be offered before you have to provide them with a plan backed with consequences for not following through. It is an employee that I don't want to lose because of their contributions, but it is also an employee that I can't afford to keep because (without changes) they are a liability. Unfortunately, previous interactions suggest that I will have to cut my losses. Yet the ball lies entirely in their court at this point because they are the one who has to take ownership for the issues they create.