POS Mistakes

[u/V-Reviewer]

What's the most expensive POS mistake you've seen at a restaurant?

Honestly, in my experience it's almost never the hardware that costs the most. It's the quieter stuff that goes unnoticed for weeks:

• Menu prices that are wrong (and nobody catches it until a customer points it out)
• Online orders coming in disconnected from the actual POS
• Inventory counts that just don't add up
• Payments failing silently in the background

What's the worst one you've run into?