I've had to make that tough choice. The "do I go now and RISK potentially either missing priority boarding and thus overhead space, or boarding cutoff, or just wait and go while on board". It is a decision not to be taken lightly. #1 is a 50/50 shot, if I've checked a bag then I'll take the terminal 99/100. #2...boy, that's a tough call, I don't like to be rushed, but MOST airplane bathrooms are terrible. That being said the front Business lav on the Asiana 380, it's better than my home bathroom!

Back to the original topic...

I wasn't on the flight, but I work at the airport...after a contract changed hands, the new company was understaffed and under prepared. A handful of flights at the start of the day were delayed simply because "the ground handler has no staff".