Based on Fulfillment Policy 5.1, If an order is not fulfilled in 5 days, it will be refunded and the associated product may be disabled.
Addendum: Effective August 15, 2018 00:00 UTC, the merchant will also be fined $50 per auto-refunded order.
Where can I see which orders have received fines?
To view all fines, check out the link here. From there you will be able to filter all fines for your orders.
You can also go directly here to view all unfulfilled order fines.