Thanks for reading and for the kind words.

Here’s the way that I think about it:

An injectable is a class that is specific to your application — one that you wrote or one that is part of a class library that you are using that is specific to your application. They are classes that are part of your domain.

Creatables are classes that are common to many applications — runtime-library stuff, common libraries, etc. They are classes that are not part of your domain.