I design embedded products for industry and usually prototype with Arduino and Pi-alikes before designing the final board. A custom board assembly is much chea

I design embedded products for industry and usually prototype with Arduino and Pi-alikes before designing the final board. A custom board assembly is much cheaper to manufacture. For instance, for a recent design, the only chip used off a full Arduino board was the microcontroller itself (and then in a different, smaller package). Physical and electrical constraints are often significant. And that's before getting into all the issues involved with firmware and IP. I love the idea of open-source (hardware and software) consumer appliances, but everything is stacked against it. Primarily economies of scale.