This automation re-checks with Stripe for every order still sitting in a pending state (Twint or 3-D Secure confirmation). If Stripe now reports the payment succeeded, the order is marked paid and an order-paid bell notification fires. If Stripe reports it failed, was cancelled, or needs a new payment method, the order is auto-cancelled and an order-cancelled bell notification fires. If it's stuck waiting on the customer to confirm (3-D Secure), the customer is emailed a "continue your payment" link and your store's admin address is emailed too — but at most once per day per order, so the same stuck payment doesn't re-email you every time this automation runs.