They also have more frequencies. E.g. Porter flies once a day YYZ-SFO. Air Canada has ~5 flights on the same route, plus various options via YVR or YUL. As bad

They also have more frequencies. E.g. Porter flies once a day YYZ-SFO. Air Canada has ~5 flights on the same route, plus various options via YVR or YUL. As bad as they are, it's good to have options for cancelled flights or changes of plans. AC know they are the only game in town which is why their service can be so bad. On routes where they have competition, particularly long-haul to Asia, I understand their product is much better.