[folmar]

The biggest win is not the bandwidth, it's that you have exactly what was used before in case you need it (audit/postmortem), or origin goes away.

[richbell]

In the context of GP's comment bandwidth + proxies seems to have been their motivation. Not to mention that external package registries HATE how many large organizations hammer them with the exact same traffic every time a build is running, due to the lack of the local cache.

But you are correct as well; that is an uncommon yet hugely beneficial reason to have an internal artifact repository.