While I don't want to deny the right of people who want to get onboard a ship at 11:00 a.m. (arriving at the terminal at 10:00) - I have never understood wanting to get to the terminal, wait until when ever they open the check-in (sometimes 11:00, sometimes later) then wait post-checkin again because they are not boarding the ship yet.
There are usually 1-2000 people waiting at 10:30, - ridiculous.
Why? Just to get on a ship where all you can do is go to the buffet and babysit yuour luggage until your room is ready?
I always advocate getting to the ship a little later so you can avoid the crowds and go directly to your stateroom. Is it really worth battling 2000 other people and waiting three different places for things to open when you could just arrive and breeze right through straight to your stateroom?
The only time I arrived late and was perturbed was on Seabourn when we arrived at 12:30 only to be checked in, and then placed in a waiting room (with a coffee urn and some danish) and then told it would be 90 minutes before our stateroom would be ready. THAT WAS A SURPRISE FOR A LUXURY SHIP.