Generally the reason they fail in the job is, you made some...

Generally the reason they fail in the job is, you made some mistake in the hiring process in that you didn't match... them to the needs of your company accurately enough. That's the #1 reason this fails. And that's generally a good place to start: Here's where we are and here's what I didn't recognize about us and about you when I made the decision, and now it is what it is.