I hate the stress of getting to the airport, parking, getting through security, etc. There are too many horror stories of things that have gone wrong (like the time the car broke down or crazy delays with security, etc). I have had several flights where I thought I was an hour plus early and barely made my flight.

But once I get through security, I enjoy the people watching, sitting down and enjoying a book or snack, using a more comfortable bathroom, exploring new airports, etc.