There are a of factors that go into the salary of a head coach.  Coaches that were hired several years ago and are working under extensions will tend to have lower salaries than recent hires for equivalent-priority programs (e.g. Alabama and Tennessee), partly because the extensions aren't as susceptible to the recent salary bloat of new hires.  Also, the new hires sometimes need sufficient "incentive" to move to a school, and so they get huge salaries despite having done nothing for the program yet; Saban is the archetype for this.

HC salaries are also more than simply compensation for the coach.  They serve as political and recruiting messages.  Alabama, by paying Saban way too much money, send a message that they're willing to go to any length to try to win, and that money is no object whatsoever.  UT prefers to devote more money to the recruiting campaign directly, and has one of the biggest recruitment budgets in the country.  (That's a significant part of the reason Fulmer can go after other schools' "commitments" so aggressively - he can afford the late-term travel budget.)

The salaries also say a lot about the coach themselves.  JoePa's recently divulged compensation only runs around $500,000 per year.  He could easily be getting in the millions but he simply doesn't think he needs it.  I may not care for the guy, but that does impress me and I'll give him props for it.  Compare again to Saban (gee, he's an easy example sometimes).

Finally, the market competition for a coach at the time of hire/raise/whatever will dictate a large portion of the salary.  Les Miles made out like a bandit because LSU was afraid that Michigan was going to take out a double-mortgage on the Big House to bring him in.  They offered a deal that they didn't think Michigan would match along with a short signing window to pressure the closure.  If it wasn't for the Michigan connection, that deal could easily have been 0.5 to 1 million fewer dollars per year.

There's more reasons, but these were a few that popped in mind when I read the chart.

that Fulmer is right about where he should be.  He's earned his paycheck by winning a National Chanpionship, a couple of SEC titles and has been in 4 of the last 7 conference title games.  Granted he didn't win any of them, but he still got us there, and that's more than a lot of coaches in any conference can say.  

Furthermore, Miles will certainly have a higher salary at LSU after the National Title game and Richt's salary is about even with Fulmers, even though Richt has nothing but a conference title under his belt.  

Considering Fulmer is the longest tenured SEC coach, has multiple championship rings and he doesn't have an absurd salary like Saban or Meyer (who have comparble resumes over a shorter period), I'd say we're almost getting a hometown discount... almost.  Tennessee was consistantly dominant in the 90's and is consistantly good in the 2000's.  

In 15 years if Meyer and Saban are still coaching at their respective schools with as much success as Fulmer has had at UT, I'll be surprised.  And if they don't well, then I think we'll all realize we got ourselves a pretty good coach and we've been pretty fortunate.  

Cost/win is as meaningless as Cost/loss.  Are Urban Meyer and Mark Richt "bad values" because their cost/loss both exceed the $1M mark?  Flip that around to the Orgeron...is he a "good value" since his cost/loss was $100K?

Hooper stated it best, above.  It's a complex, often non-mathematical, equation based upon numerous factors that are all tossed into the free-market.

Personally, I feel that virtually ALL D-I football coaches are overpaid, including The Papa.  However, I would prefer (like most others) to have an drastically overpaid SUCCESSFUL coach in lieu of a coach that is paid $65K/yr that can't win a game.

It also means that Bobby Johnson from Vanderbilt was omitted from the table.