Take 2015. Say we beat UNLV instead of losing to Missouri in Kansas City. BYU was receiving votes and had climbed to #27 or 28 right before the Missouri loss (and that was with the UCLA and Michigan losses on our record!). BYU would have likely finished the regular season 10-2 and ranked - and plays for the MWC championship.
Now, let's say we beat UConn in the OOC and don't even play Michigan - BYU was ranked #19 going into that Michigan fiasco. BYU may be finishes 11-1 and in contention for an NY6 bowl, regardless of whether we win the MWC championship.