The number 7 is often seen as lucky in slots and pop culture because it appears...

https://www.runway-bookmarks.win/the-number-7-is-seen-as-lucky-in-slots-and-pop-culture-partly-because-it

The number 7 is often seen as lucky in slots and pop culture because it appears frequently in classic slot symbols like 777, which signals a big win. Its luck may also come from the seven-day week, a familiar cycle people trust and recognize