Going on a date is the same thing. If a date is at 11 am, both show up earlier like 10 minutes late. When they do meet up, it sometimes goes like "Did you wait long?", then "No, I just got here." to be polite as being late means you don't think to highly of them as they aren't worth your full attention.
Japanese take punctuality very serious
It's considered rude and disrespectful to arrive late
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