Despite all the advancements smartphone companies have made on the phone, desktop platforms continue to be their preferred way to buy stuff online. CNET spoke with a number of people who not only confirmed that they bought things using a laptop or a desktop computer, but also listed the reasons why they don't use their smartphones to do big transactions. From the report: For now, though, buying stuff on a phone is often terrible, so at least for this Cyber Monday you're likely still buying stuff on a laptop, with its big screen and full physical keyboard. While people are buying on mobile websites and apps a lot more -- up 65 percent from last year -- consumers are three times more likely to complete a purchase on a PC than a phone, according to an Adobe mobile retail report released last month. That's resulted in PCs bringing in 75 percent of retailers' online sales this year, versus just 16 percent from phones, the report said. To consumers, phone screens are too small, pinch-to-zoom features aren't available in mobile apps, it's hard to find things easily, and checkout using that tiny touchscreen keyboard is a pain. When people do buy on mobile, they make smaller purchases than on desktops, Adobe found. Retailers stand to lose billions of dollars in sales if they don't get their act together, Adobe said. And consumers will continue to be frustrated when trying to buy.