What do you propose is at fault? The fleet is brand new so maintenance delays and cancellations are minimal. The airline routinely has days where on-time arrivals within the allotted 15 minutes are at or above 90%, thus it isn't as if the airline is incapable of running on-time. FWIW, there is an internal effort to minimize the few controllable delays we do encounter and to decrease boarding time and turn time. It is all too easy to use the DOT statistics in fallacious ways and I'm not sure why you're using them to crucify an airline.
joe