The technology's accuracy rates decline in stores with too many products that are similar in appearance, he said. And the hardware, which includes hundreds of cameras, is expensive and generates significant heat. Amazon Go's cashierless technology has been widely touted as the future of retail. But one former Walmart executive says the technology, while impressive, has too many limitations to succeed in grocery stores, department stores, and other retailers with stores that are generally larger than a gas station. Read more: Ex-Walmart exec says theft helped kill Walmart's cashierless checkout technology. When Larson left Walmart, he joined Innowi, a company that makes handheld mobile checkout devices. In an interview with Business Insider (and later in an article posted to LinkedIn), Larson outlined several reasons why he thinks Amazon Go's technology won't be widely adopted by most retailers.