[jhartmann]

He did reuse things that exist inhouse, like the face recognition piece. To rebuild a service with Google/Facebook/Microsoft/Amazon level accuracy in that task, it is definitely more effort than 100 hours by itself.

To use an existing private service, not nearly as much effort.

That being said: Of course he could have learned how to train a model himself, but even in that case he is using training infrastructure and data that is available to him that is not public. I highly doubt he had the time to build those sorts of things himself. But his goal was more talking to his home and using tools to build an interactive home assistant. Sounds like he was very successful at doing that. He wasn't out to build the individual AI pieces, doesn't make it not cool or interesting.