It also varies by culture—e.g. in central and southern Italy it is considered socially acceptable to be a bit late at a meeting, but everybody knows that so if they want to meet you at 11:30 they will tell you to meet at 11:15, or 11:00, depending the level of formality of the meeting. If they were somewhere where being even slightly late is considered rude, they’d tell you to meet at 11:30.
It also varies by culture—e.g. in central and southern Italy it is considered socially acceptable to be a bit late at a meeting, but everybody knows that so if they want to meet you at 11:30 they will tell you to meet at 11:15, or 11:00, depending the level of formality of the meeting. If they were somewhere where being even slightly late is considered rude, they’d tell you to meet at 11:30.