In a technical, ideal sense the PoS is the source of truth. But life is messy.
PoS may lose connectivity. PoS may be running an outdated version of the software. PoS is based on some unreliable operating system or low-end PC, and is unreliable. PoS doesn't know about the store manager's last minute special because the distributor sent too much stock. Stores don't have in-house IT guys.
From a legal standpoint, in some states, the price on the shelf label is the source of truth. My grandmother lived in a state where if the price on the shelf was lower than in the PoS you got the item for free.
She was very good at catching those errors and complained bitterly when the law was changed so that the customer only got the lower price.
In a technical, ideal sense the PoS is the source of truth. But life is messy.
PoS may lose connectivity. PoS may be running an outdated version of the software. PoS is based on some unreliable operating system or low-end PC, and is unreliable. PoS doesn't know about the store manager's last minute special because the distributor sent too much stock. Stores don't have in-house IT guys.
From a legal standpoint, in some states, the price on the shelf label is the source of truth. My grandmother lived in a state where if the price on the shelf was lower than in the PoS you got the item for free.
She was very good at catching those errors and complained bitterly when the law was changed so that the customer only got the lower price.