What makes a good pep talk?

I've opened an email list to send weekly motivational pep talks to other independent creatives who still haven't "made it".

I struggle with self doubt a lot in this indie life, but I have found that for me, a pep talk that is grounded in hard-to-deny truths is very effective for clearing that doubt away.

Rather than just going for empty "feel good" platitudes, I try to persuade myself logically into a more positive mindset.

I want to improve the quality of my pep talks now that I'll be writing for others as well, so I'm wondering, what do you think of pep talks?