At least once a month a friend will ask you to put him in your trolley.
When passengers stand after landing before the seat belt sign is off you'll always wish the pilot we'll hit the breaks.
The plane will have a mechanical problem on a round trip only when you forgot to put clothes in your trolley.
Someone will always offer you a flight in exchange for a flight you really want. When you have a flight you don't want you'll never find a swap.
p.s. - é incrível mas isto é mesmo real, (quem faz disto vida, sabe) são alguns dos clichés desta profissão.