You can basically cluster college programs into various tiers: national title contenders + those who seriously want to be, P5 conference title contenders and those would would be, respectable P5s, you get the idea. Focusing on the national and conference title contenders, the platonic ideal is someone who has head coaching experience and is a proven winner at that level, i.e. they've already won P5 conference titles or national titles.

Problem is, there's very few of those out there, and they have huge price tags associated with them. So, you end up either taking a coordinator from a proven winner, or a head coach from a winner at a lower level, either of which carries the risk that they won't actually be able to replicate the success they had at their previous job, for lack of experience. Even big-time programs--Oklahoma, Georgia, Ohio State, Texas, Florida--have all done this at some point in the past couple decades. Sometimes it worked, others not so much. Honestly the only P5 proven winner head coaches I can think of recently who got hired elsewhere within the sam tier are Jimbo Fisher and Jim Harbaugh. UCF getting Gus Malzahn is a higher-to-lower tier move that's as strange as Buzz Williams to VT was at the time.