How (not) to prioritize (airline) internet traffic

United Airlines president Scott Kirby is obsessed with making sure that flights depart on time. His obsession provides an object lesson in how not to run a network or, more precisely, in the importance of using the right metrics both to understand how to think about network performance and to realize network performance. Frequent fliers understand the problem with Kirby’s obsession with on-time departures: Fliers care more about on-time arrivals than departures, and pushing flight crews to depart on-time leads to poor customer experiences. (Chip-on-the-shoulder disclosure: The two worst experiences that I have had flying have both involved flight crews cutting corners in efforts to make on-time departures — once needlessly stranding passengers at airports and once boarding a plane before the pilot was even available for the flight.)