Here the reasons are not just performance.
Fox walked because he wouldn't turn up the intensity. He then tanked in Chicago and is unhirable.
Kubiak retired because the loaded roster he inherited was crumbling, as was his health. Again, not something performance related.
VJ was hired and then retained a second year. This is pure performance.
The analogy doesn't work that well, imo. But, truly you are smarter than I am.