No one is immune to a bad hire, or even a series of bad hires. The biggest fallacy in sports is that resources + history = championships. New York Yankees, Boston Celtics, Alabama football.,, some of the most historically great franchises with seemingly unlimited resources have gone through extended periods of mediocrity because they bought in to the belief that all things would continue to be great for them just because they expected them to.
Plug and play GM’s/AD’s, coaches/managers, players who were individual greats but never bought into the team concept. High profile hires that are based more on Q rating than qualified experience. But the biggest mistake made over and over is recognizing that things have gotten stale, bringing in a fresh face, and then hamstringing them by insisting that they do not stray from the plan that was no longer working.