I have always seen traditional songs as the templates on which my own efforts are built. Originality (if it is that) comes in when you try to do something, which you do not already have exactly the template for, or which you need new tools to finish. That is why it emerges at all. You don't set out to be original when you make something. The priority is to end up with something good. If you can't finish the job without doing something different to what has been done before, you find your own solution. I think that is where the originality emerges by itself.
(Of course, we usually discover later that someone somewhere has used the same solution for something else).