You really have no idea how airline scheduling works. A typical trip pairing for a cockpit crew is for 4 or 5 days going all over the country. Start in Atlanta,

You really have no idea how airline scheduling works. A typical trip pairing for a cockpit crew is for 4 or 5 days going all over the country. Start in Atlanta, fly to Miami, back to Atlanta, then to Vegas, sleep there, next morning back to Atlanta, then on to Phoenix, and back to Atlanta again, on to Houston and sleep there. Etc etc for 4 days in a row. So a problem in Miami could easily cause delays and cancellations on a flight that to you looks totally unrelated. The only reason you have less impact in a traditional hub and spoke system is that there are extra aircraft and reserve crews in the hubs (some are at the airport, some at home at a few hours notice) and every other flight passes through the hub. So if the Atlanta to Miami and back thing goes really wrong, another crew and aircraft will fly the Atlanta to Vegas flight and sometimes the rest of the trip. Doesn't happen for a simple delay, but if the delay pushes the crew over their duty time limits on the outbound flight for example the return to hub would be cancelled and a reserve crew would pick up the next flights starting from the hub. The timed-out crew would go to be hotel and fly back as a passenger with the next days flight.