Fountainhead worked on me a bit. I still think integrity and innovation are important, but I bet I would have gotten that way even if I hadn’t read it.
I don’t make weapons, I don’t work for Twatter or Faceboot, I do make an effort to keep refining and upgrading designs instead of endlessly recycling the old, I do pull out dead useless code. I don’t win every battle and I don’t even fight every battle. And very generally speaking I do think if you do work you are proud of you will be happier.
At the same time you should not assume you are the smartest person and if everyone is doing X you need to at least consider that they are on to something.
See? You don’t need a 400 page novel. A paragraph works.