Movies
You take someone to the airport, its clearly the beginning of the relationship. Thats why I have never taken anyone to the airport at the beginning of a relationship.
— Harry Burns • When Harry Met Sally...

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker claims that taking someone to the airport obviously signals the start of a relationship, and so has deliberately never done it early on. It's a quirky personal rule, argued with confident, tidy logic that sounds oddly like a theory about romantic timing.
Context reviewed