This makes sense to me. I think the word "robot" has some historical/cultural connotations that lead us down this rabbit hole of defining what a robot is. Rosie from the Jetson’s? R2D2? FANUC industrial robots? It’s tempting then to cherry pick one’s own definition of a robot, and point out challenges and theorize why it’s hard to build profitable robot companies. The question is fallacious.

In general, I think the hardware business is hard for all the reasons you mention. Or better stated, the hardware business has characteristics that make it difficult to get right the first time (more important in hardware than software, I’d argue) and scale. It’s not inconceivable for a single (or a small team) to build a useful software product that makes money (several successful mobile apps, companies like 37signals, etc.). It’s difficult for me to think of similar hardware analogs (I’d love examples!). This isn’t to say that scaling software—building companies like Google–isn’t incredibly hard. It is. But for a hardware company to even have a chance, it needs a minimum scale threshold from the very get-go (besides all the other things that any business needs – a useful product, luck, etc.).

I used to work for a large aerospace company in the early/mid 2000s, and the products we built were useful, and amazing (hunks of metal weighing tens or even hundreds of thousands of pounds flying in the air transporting people). I was absolutely awestruck by the fact that upcoming companies like Google and Facebook (which were “just websites” in my then-naive worldview) had fewer people, and made way more money than us.