I bought something at Walmart. (I apologize.) The lines were long, except at the self-checkout counters. I'm sure you're familiar with self-checkout. Typically, a single human being can monitor four self-checkout aisles, continuously solving checkout computer problems. That's a lot better than hiring four cashiers.
In this case, the customer ahead of me had checked out his ten items and was attempting to pay with three Walmart cash-gift cards. Only one of them would scan, $10 out of the needed $28. The fixit guy came over and tried; and he tried and he tried, to make the cards scan. I stood right next to them, trying not to look impatient. After all, the customer had scanned all his items. It wouldn't be fair to make him go to a cashier and start all over again.
I was wrong, it IS fair. The fixit guy entered his ID# on the self-check computer, and his password. I have them right here, they printed out on my receipt:
STORE #: 2171
ID #: 9643934
I mean it, his password printed out on my receipt!!!!!! Anyway, the point is, the transaction was SUSPENDED so that it could be continued by a real cashier who could handle the gift cards. And meanwhile I got to do my checkout, without needing help from the fixit guy. I'm really impressed by Walmart's security.