Here's my thinking, I know we get caught up in getting the proven, home run hire, its honestly a crapshoot and why there's no exact science in getting a sure-fire winner. Obviously, there's greater risk with some hires than others, but at the end of the day, you really don't know. Outside of Urban Meyer, Bob Stoops, Chris Peterson, everyone we'd hire (yes, that includes Matt Campbell, Luke Fickell, Mario Cristobal, or an established head coach) has the risk of failing here.
Take a look at dubbed P5 winners of the coaching carousel the past few years and think about how a lot of them they panned out. While some worked out great, most either failed or had mediocre success.
Ones in bold are ones that I recall being the "hot", can't miss hires for each year.
2012-2013:
Arkansas - Bret Bielema
Texas Tech - Kliff Kingsbury
NC State - Dave Doeren
Colorado - Mike Macinetyre
Wisconsin - Gary Anderson
Cal - Sonny Dykes
Auburn - Gus Malzahn (probably the only one this coaching class that worked out like they had hoped and even that's debatable, also a unique situation where he already had his fingerprints all over the program from being a coordinator there 1 year prior)
2013-2014:
Texas - Charlie Strong
USC - Steve Sarkisian
Penn State - James Franklin (worked out)
Louisville - Bobby Petrino - some success, but obviously crashed
Washington - Chris Peterson (worked out)
Vanderbilt - Derek Mason
2014-2015:
Michigan - Jim Harbaugh - (I'd say mostly worked out, but definitely not to the level everyone was expecting)
Florida - Jim McElwain (went to two SEC titles because of Butch, otherwise would've been fired sooner)
Oregon State - Gary Anderson
2015-2016:
Miami - Mark Richt (so-so)
VT - Justin Fuente
Iowa State - Matt Campbell (worked out)
Syracuse - Dino Babers
Virgina - Bronco Mendenhall (so-so)
2016-2017:
Texas - Tom Herman
Minnesota - PJ Fleck (so-so)
Oregon - Willie Taggert
Purdue - Jeff Brohm
Baylor - Matt Rhule (worked out)
Oklahoma - Lincoln Riley (doesn't really count given he was in-house and a successor)
2017-2018:
Florida State - Willie Taggart
Nebraska - Scott Frost
UCLA - Chip Kelly
Texas A&M - Jimbo Fisher (worked out, but this was also a unique circumstance where Fisher/FSU were wanting a mutual break-up. Additionally, people laughed at the guaranteed money they gave Jimbo to get him).
Mississippi State - Joe Moorhead
Florida - Dan Mullen (worked out)
On the flip side, look at the ho-hum or poor hires for those years, ones in bold are ones I recall people being like "WTF":
2012-2013:
Tennessee: Butch Jones
Kentucky: Mark Stoops (success)
Purdue: Darrell Hazell (SBNation actually called this a great hire)
Oregon: Mark Helfrich (success initially)
BC: Steve Addazio (so-so)
Syracuse: Scott Schafer (didn't work)
2013-2014:
Wake Forest - Dave Clawson (given WF's history, I'd say this was a success)
2014-2015:
Pitt - Pat Narduzzi (so-so)
Wisconsin - Paul Chryst (success)
Nebraska - Mike Riley (didn't work)
2015-2016 - this was a rough year for all coaching hires:
Georgia - Kirby Smart (this is unique, some say UGA made a homerun hire by prying away Saban's top assistant, others say it was a ho-hum hire. Additionally, while the record is very strong, people, including UGA fans, believe he has underachieved)
Mizzou - Barry Odom (so-so)
Illinois - Lovie Smith (likely didn't work)
USC - Clay Helton (varying results)
Rutgers - Chris Ash (didn't work, but tough for anyone)
Maryland - DJ Durkin (didn't work)
Minnesota - Tracey Claeys (internal promotion mid-year)
2016-2017:
LSU - Ed Orgeron (while I know he's not a great head coach, he somehow managed to bring LSU a natty, plus a trip to an NY6 the past two years).
Indiana - Tom Allen (success- but was also an internal promotion)
Cal - Justin Wilcox (so-so)
2017-2018:
Oregon: Mario Cristobal (success)
Oregon State: Jonathan Smith (taken a doormat program and have been respectable in short time)
Tennessee: Jeremy Pruitt (not much needs to be said)
Ole Miss: Matt Luke (odidn't work)
Arizona State: Herm Edwards (while not world beaters at this point, proved a ton of people wrong)
Arizona: Kevin Sumlin (didn't work)
Arkansas: Chad Morris (didn't work)
TLDR: In summary, it's a crapshoot and no matter who we hire isn't a sure-thing either way.