Why sometimes Dev Resources are not visible on instances?

Hi, I’m working on a plugin that creates and reads dev resources.

My problem is that I have two component libraries, and for the library A dev resources work as expected - I add resources to the main component and they appear on instances. But it for whatever reason doesn’t work with library B - dev resources don’t propagate to instances.

My question is, could someone please list all the possible reasons why dev resources might not appear on instances?