The voice scolds you like a disapproving mother: "Unexpected item in bagging area." Then the traffic light of doom above your terminal starts blinking, letting the entire store know that you gambled in the self-checkout game and lost. What had seemed like a timesaver has turned into a lesson from the attendant you were hoping to avoid all along.
"Self-checkout lanes are like the left lane on the freeway and should be reserved for people who are fast and know what they're doing," said Sara Serie of Plymouth. "If you're on the phone, have a cart full of large items, then don't even think about using the self-checkout."
Many shoppers say the automated process saves time and eliminates the burden of trying to make small talk with the cashier. But those same shoppers have plenty of gripes, as well: other customers taking too long, no help available and, of course, machines that are either too hard to figure out how to use or don't work properly.
There's even a support group on Facebook for people who hate self-checkouts and are "sick of merchants making us do the work for them."
Obstacles aside, self-checkout machines are here to stay. There are more than 200,000 of them around the world, with that number forecast to reach 335,000 by the end of 2020, according to London-based research and consulting group RBR.
The DIY registers can be found everywhere from Walmart and McDonald's to CVS and Urban Outfitters. Shopper satisfaction of the self-checkout process varies, but according to a recent consumer survey from the University of Chicago, only 25 percent of shoppers like automated grocery checkouts, whereas 50 percent strongly prefer interacting with a live clerk.
University of Minnesota student Courtney Nelson expressed frustration over the high number of self-checkout lanes at the Target in Dinkytown.
"Buying fresh produce in an automated lane is the worst," she said. "I hate having to look up all the codes for everything, so I almost always go to the cashier."