[epups]

There is a neglected aspect here, which is internal expertise. By choosing to build, even if ultimately you end up choosing another tool from a vendor, your team picked up many important skills to be able to evaluate costs, architecture and performance. They also might be able to better customise the tool to your application. This expertise might end up saving money in the end.

I think this analogy is best suited for training models. Even if you had access to OpenAIs datasets right now, I don't think it would make sense for you to train them, except if you are a 500B+ company. Training costs will likely go down with time though, so at some point this might change.