I once missed a flight from Phnom Penh to Hanoi because the unrelenting traffic severely delayed us - even though we were told by locals (!) that leaving extra, extra early was not necessary. Security lines at the small airport were nothing compared to what I'm used to in New York, and certainly, getting through security took only a few minutes at most. 

But I lost the money I paid for the original flight and was stuck at the airport for the next few hours negotiating seats on the next available flight. It's a rookie mistake, made worse by the fact that locals told us the traffic wouldn't be bad and that we wouldn't need the extra time, but always outlook more time than you think you'll need, and then add some more extra time for good measure.

• Never underestimate traffic, especially when trying to catch an international flight

How late were you for a flight because of traffic?