So I was at the grocery earlier. I noticed after scanning that one tomato can was dented so I was moving it away. However the machine detected the bar code. And then detected it again with every move, resulting to four scans.
I asked the staff for help (she was standing there, I assumed she was monitoring the self-checkout counters and helping if there are problems) and she said,
"Never put your items in front of the scanner!" in a stern voice.
Then she said, "Now I have to remove them one by one!" in a stern voice still.
I was surprised (actually more shocked because of her tone), and mumbled my apologies.
Now I realise I was wrong and it must be annoying to her, but uhm, it's her job to troubleshoot problems that arise in the self checkouts?