Well, you should spend more time on "specifics".
We don't spend more on basketball than Wisconsin, let alone even close to evenly with Wisconsin. Wisconsin is 4th in the Big Ten in spending on basketball - we are 9th. Rutgers spends more on basketball than we do.
Texas Tech spends nearly $1 million more on head and assistant coaching salaries. Outside of coaching, Texas Tech has 2 additional positions on its basketball staff than what Purdue has, and also has a dietician and 5 more graduate assistants than Purdue has.
Also, I find it humorous that you list some of these programs as up to your standards (i.e. better than Purdue). South Carolina has been to the NCAA Tournament one time in the last 14 years. Currently, they are 4-7.
Oh, and South Carolina spends over a million dollars more per year on basketball than Purdue.
Purdue ranks 44th in spending on basketball. Spending certainly isn't everything. Like I said, Purdue has outperformed its spending big time, particularly with consistency of winning. But there are also realities of having sustained, high level success requiring investment. I think this is what you're actually wanting, no? The teams you mentioned, well for one aren't in the bottom half of their conference or are still investing more in areas of importance. But they also haven't sustained winning. It doesn't take much for a "flash in the pan". Consistency is the tough part. I mean Kentucky pays its top assistant (their recruiter) more than what we pay our 3 assistant coaches combined.
The part that's frustrating to me is that money can buy you some "hot name" head coach - but it doesn't mean they can coach a team and develop players (cough, Mark Turgeon, cough). Painter has shown he can do that. We have the coach down - we need to improve recruiting. A lot of that is assistant coaching and support staff - where Purdue trails significantly compared to its peers. I mean, Illinois has an assistant coaching pool that's 44% larger than Purdue's. Does that make any sense to you?