Have you missed your Southwest flight due to any reason? In such a case you must know what happens if you miss your flight southwest and what to do when you have missed your flight. Travelers can miss their flight due to various reasons, it can be due to heavy traffic, problems with baggage or security, medical emergencies, accidents, and family emergencies so Southwest missed flight is made to assist travelers with rebookings on such events. Under this policy, travelers who have failed to catch their plane and have shown up in something like 2 hours of their flight's time, will be designated a standby flight.