More than a third of travellers have had a flight experience so frustrating that they vowed never to travel with that airline again, according the the 2019 Airline Pain Index, a survey compiled by industry consulting firm Qualtrics.

The survey found that 38 per cent of frequent travellers said they have had such “dealbreaker” experiences.

Most-frequently cited examples included lost luggage (39 per cent), hidden fees (38 per cent), cancelled flights (35 per cent), unfriendly flight crews (25 per cent), and unclean lavatories (25 per cent).

On the other hand, 23 per cent of travellers said they have had customer-services experiences good enough to encourage them to fly with that airline again on their next flight.

Passenger “pain points” vary by age: flight delays are about twice as likely to make millennial-age travellers give up on an airline than Baby Boomers, for example, but younger travellers are 25 per cent less likely to quit an airline due to lack of legroom.

Baby Boomers also are far more likely to be stressed out by not having an assigned seat, the survey found.

Fifteen per cent of travellers said they had had an airline experience so bad it made them cry.