• I have searched the issues of this repo and believe that this is not a duplicate.

Issue

It isn't clear what the --no-cache flag does. The documentations says it disables "source caches", but it isn't clear what those are.

I was expecting something along the same lines as the --no-cache-dir flag for pip install, but it seems it doesn't behave that way. Is there something else we should be doing to empty caches for container image builds?