Regardless of what happens when from this point forward, Mack's refusal to aggressively and proactively address the vacancies in his coaching staff has adversely affected public perception in a way that will almost certainly have lasting consequences.
Those consequences might take any or all of several forms: recruiting defections, player transfers, reduced season ticket sales and athletic department contributions, diminished negotiating clout, etc.
I have no doubt that Mack is working behind the scenes - albeit at his own pace and in accordance with his own emotional comfort level - but for players, recruits, and fans, it's only natural to perceive Mack as fiddling while Rome burns.
Association with UT football will always impose some cost. Players expend their athletic potential, and they incur an opportunity cost equivalent to their athletic and academic achievements at some other school. Fans incur the typical direct and indirect costs of being a spectator, as well as the not insignificant opportunity cost of spending their leisure time doing something else. All of that makes Mack a salesman in a very real sense, and like all salesmen, Mack is ever and always communicating a value proposition whether he realizes it or not.
With each passing day, Mack's inability or unwillingness to name replacement coaches is perceived by those to whom he's selling as negative value. That's bad enough, but in addition, it turns out that negative value is considerably worse than positive value is good.
In 1979, two Princeton psychologists, Daniel Kahneman and Amos Tversky, published the seminal paper in behavioral economics. Prior to Kahneman and Tversky (K&T), economists had simply assumed that when faced with a series of potential outcomes, an individual's preferences were cumulative and linear - in other words, winning $10 was eleven percent better than winning $9, just like losing $10 was eleven percent worse than losing $9.
Using experimental data, K&T showed that humans don't actually think that way. It turns out that we attach inordinate significance to losses, such that the marginal increase in utility from winning $10 as opposed to $9 is significantly less (in absolute terms) than the marginal decrease in utility from losing $10 as opposed to $9.
In other words, we as humans will do more to avoid loss than to achieve gain.
The practical import of K&T's discovery is that we can influence another person's decision making process (read: spending) by the way in which we communicate our value proposition. K&T called this "framing."
The tie-in is obvious.
Mack's delay in naming successor assistants - regardless of the reason - casts him as ineffectual and indecisive. It raises doubts and questions, fairly or unfairly, about what it's really like to coach or play for Mack Brown. For the head football coach of the richest and most powerful program in the entire NCAA, this is the worst possible framing.
Despite all of the built-in advantages UT enjoys, Mack will soon face the prospect of losing customers (recruits, players, and fans) to distinctly lesser value propositions. Unfortunately, the marginal utility offered by UT football at present is negative, and K&T instruct that Mack will at some point have to offer even greater positive marginal utility to overcome the damage he's caused to the brand.