ORDERS counts order lines placed for that meal on that delivery date at the current kitchen - it counts lines from checkouts (completed orders), not items still sitting in someone's cart. Subscription order lines are included only when the subscription's delivery for that date is still active in the schedule (a skipped or paused subscription date is excluded).

The number matters beyond information: when you clone a menu, meals on the target date that already have at least one order are never removed, and it tells you at a glance whether removing a meal from the menu could affect customers who already bought it.