[lixtra]

Maybe it makes more sense to look at concrete examples. Twitter using the db as router (and rails in general), was a reasonable decision for the MVP. They got it fast and cheap.

For social media kind of traffic it became inadequate at some point and the debt had to be paid (and thanks to success was easy to pay).

To me a smart use of technical debt.

[dub]

A concrete example might be choosing a database and schema for a public-facing product with the hope that it'll become popular but with no architectural contingency plan whatsoever for how to scale up that data storage in the event of success

Certain qualities or features like horizontal scalability and security can be relatively inexpensive to design in at the beginning and immensely expensive to try to tack on later once a system is already in wide use.