Two reasons why I always board first:

1) Overhead space.

2) Meal selections.



If the airline could GUARANTEE that I would have space above my seat for my luggage, AND that I would get my first choice of meal on every flight, then I absolutely would board last in order to spend as little time in the metal tube as possible.

But the airlines certainly wouldn't guarantee either.

So I'm always among the very first passengers to walk on board, if not the actual first.