There's luck in sports. Every team that wins a championship or goes to a final four in college basketball gets some degree of lucky. Most who make the Sweet 16 do as well.
My line of work (poker) gives me a unique perspective to analyze that sort of thing. If I go into a hand as a 70/30 favorite and win the pot, I ran above my expectation by winning 100% instead of 70%, although winning 70% would be impossible.
Likewise if we had a 90% chance of beating SDSU, a 60% chance of beating WVU, and a 20% chance of beating U of H, our expected wins through three games would be:
.9 + (.9 * .6) + (.9 * .6 * .2) = 1.548
Then 10.8% of the time we'd still be playing and thus our total expected number of tournament wins going into the tournament would be a little higher, maybe 1.65 or 1.7.
You could approximate this during any tourney run, using a variety of methods from qualitative analysis to betting lines.
Anyway, any time you exceed that number you got lucky. Any time you fall below it, you were unlucky. In the long run you'll likely end up near the sum of the number if you're estimating well. The real luck is bunching wins. I'd rather win 6-0-0 over three years than 2-2-2. We got a little lucky to bunch some wins in a Final Four run. That doesn't take anything away from the players/coaches.