I'm happy to provide my take on your question, but let me preface this by saying I'm admittedly biased. I knew Joe Tiller pretty well and watched his frustration as the university didn't step up to support football at a championship level in the way that they're starting to do now. So my bias is in believing that while a truly extraordinary coach in football or men's bb, say a Brad Stevens, can build a championship level program with far fewer resources than their competition, those coaches are incredibly difficult to find. With most coaches, even those that are very talented and driven, the best that you can hope for is for them to somewhat out perform the station of your program.
Given my bias, while it's frustrating and disapointing to me as a fan to see Purdue fall short in regular season and tournament conference championship bids and fail to advance deep into the NCAA tournament, I try to temper that frustration with the view that in my mind, based on resources, recruiting base, admissions, etc. there are at least five programs in the conference that are better positioned to win in men's basketball than Purdue (just my opinion, but I think it's fairly objective).
So if I'm the President and AD, I have to ask myself whether my goal is to continue what we've been doing, i.e. making the tournament most years and occassionally seriously challenging for a conference championship, or if my goal is truly to contend for final fours and national championships. If my answer is the former, I'm very greatful to have Matt Painter coach as long as he wants so long as his performance doesn't significantly decline over an extended period of time.
If my answer is the latter, I figure out what resources, i.e. $$$ it would take to get to that level and decide whether I'm willing and able to make that commitment. If the answer is yes, I sit down with Matt Painter and clearly communicate that these are our new expectations tell him that he has these additional resources to work with to put his assistant pay, recruiting budget, etc. in the top ten in the country and ask him to come back with a plan for what changes. As part of my analysis, I also determine what we're willing to pay for a replacement coach if Matt doesn't deliver. Assuming that I'm willing to hire a replacement that's compensated in the top ten in the country, I start evaluating what type of coach I can attract for that money if Matt doesn't show signficant improvement in two years, I make the change.