Standing the same afternoon on her decks it wasn't the same, for two reasons. You may relive it in memory, or on film or sound, but that is a recording, not the primary experience. You also remember the feeling that this is a pivotal point, but you remember it as a pivotal point, not the hazy, dizzy, almost hallucinogenic feeling of the moment, the climax, the triumph, the first step, without any perception or analysis. Ships are different for other reasons. They restrict us in ways normal life does not.
Few prisons are as small as ships.
Ships do not. More importantly, the people aboard are limited by the ship. They cannot get off, or get away from each other. Like a prison they are limited to the cellmates they have chosen to be with. Whatever happens, happens only to those aboard, no-one else is immediately affected, tho' inevitably the ship must come to land.