There are two major factors at play here. First, lazy hires of inexperienced coaches. Second, an unwillingness to open up the wallet.
To the first point, lazy hires. Since Butch, we've hired 5 coaches in 18 years:
1. Larry Coker - promoted in-house coordinator, 0 head coaching experience.
2. Randy Shannon - promoted in-house coordinator, 0 head coaching experience.
3. Al Golden - head coach with a losing record from a small conference.
4. Mark Richt- established head coach with winning record in Power 5 conference.
5. Manny Diaz - coordinator with 0 head coaching experience.
Of all these guys, guess which one was the only coach to win double-digit games in the ACC and win the Coastal division? Exactly. The guy with prior experience running a winning and competitive program at a power 5 school. I don't think that is a coincidence. (yes I know Coker won double digit games but he was exposed as a failure and only did so thanks to Butch leaving him 20 something first rounders).
To the second point, money. According to a quick search, here are the above coaches highest salaries while at Miami.
Larry Coker ~ 2 mil a year
Randy Shannon ~ 1.4 mil a year
Al Golden ~ 2.6 mil a year
Mark Richt ~ 4 mil a year
Manny Diaz ~ 3.1 mil a year
I can't find much info on Coker's time around CFB, but other than that, it appears Mark Richt has been the only guy we've paid our coach an annual salary ranking in the top 32 in the country over the last 20 years.
My takeaway is this: only once have we both ponied up decent money *and* landed a guy with winning experience at a successful, power 5 program. Interestingly, he's the only guy to come in and win 10 games and his division (since the ACC move).
I submit that if at any point the decision makers have had enough and want to consistently win and put an end to this dark age of mediocrity, their only choice is to cough up the money, pay a top 15 salary and go out and get a guy who's proven he can build and sustain a winning program at high level. Enough coordinator dice rolls and enough bargain bin shopping.
There are no more half measures to be had. If any of them ever get serious about winning, amateur hour is over. Get ready to shell out 6+ million annually and go sign a whale with some big time Ws and recruiting scalps on his wall.