OK, you want details:
1. Cashiers are trained. It's not *lots* of training, but there is training. There's a reason for that training: it's easy to fuck up when you are processing purchases.: to miss items accidentally, to run items past the scanner twice, not to mention dealing with items that have no bar codes (like fresh produce).
Self check-out expects you to now to do that work untrained, which leads toโฆ
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