big 12 play and 20-9 overall and beat BYU and Kansas was 41 in RPI and might have been the first team out. Ole Miss, Washington, and South Carolina who were just behind Arizona in the RPI rankings did get in as at-large selections.
Volleyball uses RPI and KPI and Arizona had much worse (58) kpi ranking. Perhaps Arizona was also punished for weak non-conference schedule in which most difficult opponent was VCU rated 92. Arizona did have 3 name teams (Boise St., VCU, and Alabama) in nonconference, but those 3 teams aren't actually great at volleyball.
In general I agree with rewarding teams that play difficult non-conference schedules when teams are fairly similar in their at-large profiles.