Sometime in 2008 I visited a friend in Providence, Rhode Island. We went to high school together in Hong Kong and we were both now studying in America. I had a good time seeing my friend for the first time in a while, but on my way home I hit a snag.I knew my flight back to Philly was scheduled for 8 p.m., so I made it to the airport by 6:30. I like to leave plenty of time at the airport in case there are long lines for check-in or security. And this day there was a long line at check-in.Soon after I got there, airline personnel were shouting to the people in line, which included me. “Passengers for PHILADELPHIA, departing at SEVEN P.M., please come to the front of the line. Passengers for PHILADELPHIA AT SEVEN, please come to the front of the line.” It seemed unusual that passengers for one particular flight got to jump the line, but these people had less than half an hour to go before their flight, so it made sense. Then again, who would arrive at the airport only half an hour before their flight? Anyway, I was on the 8 p.m. flight to Philly, so I stayed put.By the time I had reached the front of the line, and the airline people had shouted in my direction a few more times, I started to worry. I considered myself punctual and I rarely screwed up something like a flight departure time. But the commotion set off some alarm bells in my head. Was I really on the 8 p.m. flight? I checked my ticket and panicked. Of course, there was no 8 p.m. flight.I scrambled. Having checked in quickly, I ran to the line for security screening. I had minutes before the gate doors would close: enough time to run to the gate, but not enough to wait in line for security and run to the gate. So I asked those in front of me whether I might (please) skip the line.Everyone said it was fine for me to skip ahead, except for the lady right in front of me. You see, her flight was departing in half an hour, so she was in a rush too. I explained that half an hour was plenty of time to reach her gate, so would she (please!) let me go first? She wouldn’t budge. So I waited and waited until everyone in front of me made it through security and then I passed through as quickly as I could. I sprinted towards the gate.A flight attendant closed the gate moments before I made it there. Another flight attendant looked at me sympathetically and apologized. They couldn’t re-open the gate door after closing it, she said, but she was happy to rebook me for the next flight to Philly. I thanked her and thought about what to do next. It was late and my next flight would depart early the next morning, so I decided to stay at the airport.Providence's T.F. Green Airport turned out to be fascinating at night. Around 11 p.m. or so the last flight departed and the terminal emptied out. I was literally the only person there. There were no airline staff, no guards, no food vendors, and no other passengers. Normally airports are busy places, with people running around to catch their flights, with overhead announcements, and maybe with some children crying. Without any of that, I felt like I wasn’t supposed to be there.It wasn’t until 2 a.m. that a security guard appeared. He said he’d be closing the terminal and asked me to stay land side. Air side, there had been some chairs comfortable enough to sleep in for a few hours. Land side, I had no such luck. I walked around for a while until I spotted a wooden bench long enough for me to lie down on, near stacks of napkins and coffee cup holders.And that’s how I learned not to assume you’re so good at something that you can ignore your common sense, or you might find yourself spending the night at Starbucks.