Free tier provides a lot of training material. Every time you correct ChatGPT on its mistakes you’re giving them knowledge that’s not in any book or website.

Thats a moat, albeit one that is slow to build.

That's interesting, though you have to imagine the data set is very low quality on average and distilling high quality training pairs out of it is very costly.

Hence exponential increase in model training costs. Also hallucinations in the long tail of knowledge.