That's a really good question. I thought Providence, St. John's, and Seton Hall should have made the NCAAT last season, but I don't think it was a complete outrage they were left off. Although there is gaming of the rankings systems and I do think the ranking criteria needs to be adjusted so this gaming doesn't occur as much. St. John's had some bad OOC losses such as getting blown out by Michigan by 16 pts and losing to Boston College. This invariably hurts BE teams that lose to St. John's. Villanova had some good OOC wins with some bad OOC losses and they beat Providence twice handily. I am sure that hurt Providence big time, too.
Last but not least, Creighton, who finished 2nd in the Big East, got blown out by Colorado St. who finished 7th in the MWC and against UNLV who finished 4th in the MWC but missed the NCAAT. Those hurt the Big East a ton. The MWC got 6 teams in the NCAAT. In essence, with Creighton being in 2nd place in the Big East, it made the Big East look inferior to the MWC. The many ranking systems had the BE higher than the MWC, but let's face it, the NCAA committee uses a lot of subjectivity, too, and those OOC losses for the Big East certainly did not help.