Nothing is worst than having to wait in a crowded airport for hours and hours or miss your connection flight because of a delayed aircraft. Such situations can create a lot of frustration and tension among passengers and usually lead to a lot of headaches for the airline representatives.
On-Time Performance is one of the most important Key Performance Indicators (KPIs) for the airline industry. There is a story about it being the main KPI used during the British Airways turnaround and successful privatization in the 80s by Sir John King, later Lord King. He was appointed as Chairman of British Airways in 1981 by Baroness Margaret Thatcher, with the mandate of preparing the airline for privatization.