In 2019, David Limp, head of Amazon’s devices business, saw an opening.

For years, Roku—Amazon’s chief rival in the market for devices that let you stream video onto television sets—had supplied software to TCL, one of the world’s leading TV makers, to power the Chinese company’s internet-connected TV sets. With that deal coming up for renewal, Limp flew to Berlin to pitch TCL executives on the idea of Amazon replacing Roku software in TCL sets, according to people familiar with the project. Such an agreement would have taken a bite out of Roku’s market share and given Amazon a bigger piece of the advertising and subscription dollars pouring into the streaming-video market.

Amazon cranked out a prototype of a TCL set running on Amazon’s software. But then TCL shocked Amazon executives in 2020 by saying they weren’t ready to part ways with Roku, those people said. Amazon was even more surprised a few months later, the people said, when TCL announced it would replace Roku’s software on a handful of TCL television models in North America after all—with an operating system from Google.