When I first saw a self-checkout lane at Walmart I thought it was a wonderful idea. I always thought I'd be a good at scanning items and bagging groceries. Now I had the chance to do it all myself! Soon the honeymoon would be over. Too many times I've had to wait in line at a self-checkout register for longer than I would've waited at a regular register because the customer checking themselves out couldn't figure out how to scan the item correctly. Or, they scanned the item but didn't put it in the bag "correctly" and was prompted by the calm computer voice to remove the item and then place it back in the bag. The worst of all is waiting in line as you watch the people in front of you struggle to figure out how to scan their produce. Produce items don't usually have bar codes, must be weighed, and have a special code that has to be typed in. In the olden days, only Walmart employees were privy to the codes. Now because of self-checkout ordinary customers get to weigh the produce and then struggle to figure out what to do after that. Usually the nice computer voice says you have to wait for a real employee to come and scan their id, then punch in some numbers that magically make the register work again.
Recently I was at a grocery store that has a few self-checkout lanes. I had to run out at 11:30 at night to get a birthday card. Apparently this grocery store was the place to be at 11:30 on a Saturday night. Only seven self-checkout lanes were open...zero regular employee-run lanes. I waited in the shortest line (which consisted of about 20 people) and watched the other customers struggle to pay for their groceries. I understand that with no employee-run lanes open no one really had a choice.
I decided after this trip that self-checkout lanes were never meant for more than 5 items, no produce, and nothing that is on sale or that could possibly not be scanned properly. I really try to use the self-checkout lanes when I have 2 or 3 items and never when I have produce. I've tried the produce thing. I ended up charging myself more for cucumbers because I didn't select the right type of cucumber on the list.