They really are fortunate in that they've had sustained success since the 1950s. Aside from a seven-year stretch in the '90s, they've never gone very long without an NCAA or NIT appearance. Basically the one bad coaching hire they made was the coach they had before Purnell.
We dog Gregory all the time, but even he led them to two NCAAs and three NITs in eight seasons during a stretch in which Brad was ineffective and Majerus was rebuilding. And in two of the three seasons in which his teams didn't play in the postseason, they still won 19 and 18 games.