Originally Posted by
MSPeconomist
That's a dramatic indication of how good DL's operations are.
In addition to DL's far superior operations, they may also have more routings that can be sent via multiple hubs and greater frequency on busy routes, which allows a mis-connected passenger to simply wait for the next DL flight. AA seems to have more cities with service to only one of their hubs, and more cities served with just a couple flights a day, which means more need to rebook onto other airlines.