 But while the nonscheduled airlines' fares were unmatched throughout the industry, their service quality was frequently unreliable.The low fare model required that flights be relatively full, and it was a common occurrence when flying on a non-scheduled airline for customers to learn at the airport their flight had been delayed until tomorrow so that the airline could sell more tickets.Because most companies had only a few planes and just the staff to crew them, delays as a result of weather or mechanical failure could completely incapacitate the airline, forcing it to cancel or postpone flights for which tickets had already been sold.