TIC response aside, my point is that Phil Knight doesn't have to worry about things not coming through.
Let's say you have a solid job, $100k a year and net worth of $1M dollars. You're not absolute upper crust, but you're fairly comfortable and doing well.
And it turns out that a highly touted prospect will come to BYU if you give him $15. Would you do it? There's no guarantee it works out obviously, but for such a piddling sum, might as well, right? Worst case, you're out 15 bucks. I'd probably do it several times a year every year. Support the team by budgeting $100 to get BYU 6 top prospects every year.
Now realize that $15 (to this hypothetical you) is the equivalent of $1M to Phil Knight. So maybe he budgets some tiny amount ($10M or so) to throw at recruits every year. And he hopes it works out and he gets excited when it does, but it's honestly such a piddling amount that he doesn't even worry too much about the ROI.