The closest I've ever come to missing a cruise my flights were scheduled for the day before. Because of delays, missed the connection in Chicago (which I found kinda annoying, last flight of the day for the plane, and there were 7 of us that were connecting, wouldn't have taken more than a 10 minute wait and we'd have all made it). Delays the next morning, plus some issues with traffic on the way to Galveston and a cab that wasn't showing up. Quite frankly, the only reason we made that cruise was the rental car shuttle driver that had come back from his last run and gave us a lift to the port well after the last scheduled trip. We were some of the last couple people boarding the ship.

After that experience, I'd never fly in with less than a day to spare.