It's not unexpected, you digital fuck. You literally just told me what it is. It's right there on the screen. I did the wavy-wave, you did the bleepy-bleep; up until the point where you decided to have an electronic stroke, things were going exactly according to plan. What you mean is that you haven't been programmed right. Don't go putting this on me, like I've somehow gone out of my way to surprise you. I've got places to be, man. I can't be playing hide-the-actual-salami with the Terminator's younger, shittier cousin.
Oh, and now you've sent for backup. Well done. Now I have to deal with a human person who thinks I'm either an imbecile or a thief for not being able to work what's effectively a bathroom scale with delusions of grandeur for the fourth time.
i've never even seen a self checkout that does this... it feels like it would be an enormous hassle for the store.
also we've had the little hand scanners you bring with you through the store for something like 20 years so i don't really ever go through the checkout unless it fails to scan my card.
Part of the problem is they never clean them. So they have about 3 g worth of fruit stickers, dust, random bits of cellophane and onion skin in them. So they're already starting out from a compromised position.
I know someone who developed a load of the underlying code. It's a lot of bodging, and sensors being ran past their nominal lifespan. Some of them just go a bit unreliable, and the error accumulate until it starts triggering errors.
what i mean with extra work is partially the weight thing, partially the fact that here there's usually 15-20 checkout things in larger stores, and no dedicated staff member at all unless it's busy.