As you may know, US airlines keep track of actual on time arrival and departure information and it is publicly available. Late flights arriving or departing are tracked.
A belief exists that this information helps the public select flights. The reality is that most delays are weather or traffic related and all airlines serving airports with weather or traffic problems will have similar results. Thus we have a metric that doesn’t matter.
And yet it drives behavior of the airlines. I have personally had a gate agent close the door in my face because the flight had to leave on time and she was not going to reopen the door to board me. Flight crews and ground personnel obsess about this metric to the detriment of passengers.
Recently I watched Southwest, create a delay of 20 minutes on three flights (the metric is 15 minutes is defined as late). They did this by swapping aircraft to prevent one flight from being 1 hour late and screwing up passengers on that flight from making their connections. Those 20 minute delays (which actually may have resulted in less upon arrival) dinged them on 3 flights, but allowed virtually all passengers to make their connections.
The fact that Southwest exclusively flies 737 aircraft also makes it easier for them to make that swap.
Congrats to Southwest for allowing passengers to come before metrics that don’t matter.