> That is: you need convince yourself that what you do is the best thing you ever do.
I think this is a dumb idea, a mix of wishful thinking and immature psychology. You become someone because of your competence, not of what you believe in.
We all want to do the best thing, but in practice in every project there are lots and lots of small, routine things that have to be done in order for the best things ever to even start functioning. I think its important to understand clearly what is the best, and what is necessary and see how each part contributes to the whole project.