One point that may help clarify some of the general thoughts on ‘self’ in terms of Buddhism - there is a concept of who is watching the watcher. Meaning, if you stop to pay attention to the various thoughts/biases/whatever that pop into your head and watch them flow in, who then is the true self? Are you those thoughts? Are you the watcher and not the thoughts? Are you both.

This is where the concept of self gets very sticky, and is why articles about self and Buddhism speak about the fleeting transitory nature of self and how we all evolve over time.

People in my opinion confuse what motivation is. Motivation and discipline are largely the same. It’s just making the choice to do the thing. Motivation is not always some intrinsic internal drive, while it can be, those moments tend to be fleeting.