It is partly due to the capital investment required to first achieve a competitive scale. Since microprocessor companies require such enormous investment, there

It is partly due to the capital investment required to first achieve a competitive scale. Since microprocessor companies require such enormous investment, there are fewer large companies and startups to compete for talent. In other words, the hardware labor market is closer to monopsony than the software one. In addition, other things being equal, the closer one is to customers, the more leverage one has on pricing and terms. This is a major reason why Amazon, Google, and Apple are focusing on developing voice assistants and home devices.