It's not always the passenger's fault. Sometimes you show up at the airport and there are unexpectedly long lines.
Sure, pax should arrive early enough to cover most eventualities. But what happens when the line is twice as long as it normally is because the airline is shorthanded that day, or the computers are running slow, or weather in another part of the country has messed things up?
I arrived at LGA for a US flight to IAD a couple years back and found lines with sevearl hundred people (from the coach check-in desk, through the maze, then all the way to the far end of the terminal). It took me about 4 hours to get to get to a ticketing agent.
I couldn't possibly have known that there was some lightning incident in Boston that was going to throw the whole northeast system into chaos.
Until we have some easy way of determining what's going on before leaving for the airport, it's tough to blame the pax. People who cut it close frequently will eventually get burned, but there are some innocent people who are victims of unusual circumstance.
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