Over the last thirty years, self-checkout machines have become more and more common among retailers, especially national chains like Walmart and CVS. Although retailers claim these self-checkout machines increase efficiency and help them get customers in and out of stores at a faster rate than they otherwise would if they had to go through an assisted checkout lane, we all know that self-checkout lanes are plagued with problems that can ruin your day.

While most of us can agree that self-checkout machines are a pain, they were installed in retail locations across America so companies could save money on labor costs. But there is really something you need to know about these self-checkout lanes that go beyond a standard annoyance.

“The rationale was economics based and not focused on the customer,” Sylvain Charlebois, director of the Agri-Food Analytics Lab at Dalhousie University in Nova Scotia, told CNN. “From the get-go, customers detested them.”

One analysis suggests that companies can save as much as sixty-six percent if they replace a cashier with a self-checkout machine. That’s why companies like Walmart and Target continue to invest money in making their self-checkout machines more and more popular among consumers.

In addition, self-checkout lanes often don’t work and require the supervision of a human worker to get customers in and out of the store. One study reported by CNN found that as many as 67 percent of shoppers who use self-checkout machines found that the machines did not work the way they were intended to.

Because self-checkout machines cost more than companies thought they would, some retailers are accusing innocent customers of theft or shoplifting in order to make more money from the American consumers shopping their aisles.

Lawyer Carrie Jernigan, a criminal defense attorney, turned to her 1.2 million followers on the Chinese-created social media app TikTok to reveal that self-checkout machines should be avoided at all costs. Because thieves have gotten very good at stealing from self-checkout machines, big box stores like Walmart are showing no mercy to customers who might have accidentally left the store without paying for an item.

Even if you innocently forgot to scan something or left it in your cart by mistake, these national retailers will come at you with the full force of their team of attorneys to make you pay for your “crime.” These stores are going after their customers to make it possible for the self-checkout machines to be more profitable.

“Big-box businesses aren’t going to spend their time and resources trying to figure out if you did it on purpose,” Jernigan said.

In other words, it is risky for you to use a self-checkout machine.

“So they will begin watching hours of video to see the last person who checked out with the Mario Lego set because they’re two short. And, for some reason, they pinpoint that they think you did it,” Jernigan added. “And because of who these big box stores are, they usually have to present very little evidence to get an affidavit for warrant signed, the charges that could land you up to a year in jail get filed, and then you are fighting for your life trying to determine what day you were at Walmart, what all you bought.”