These types of guys want a challenge. The challenge at Florida isn't having the things you need to be successful, it's the pressure to use those things and be successful.
Spurrier did it. Meyer did it. Everything necessary to win is there. Muschamp went 11-1 one year (lost the bowl)...the same guy who had Florida's first losing season of my lifetime. McElwain went from unranked to top 10 during a season. Mullen won an OB and had 3 straight top-10 finishes.
If those guys can have those peaks, the problem isn't the program. Great HCs are hard to find, that's all.