Nothing, your Self (or unconscious mind, you can call it) automatically directs you to do what is in your highest good. Have you noticed that the less you consciously think about something, the better you perform at various tasks? If you don't think about what you're trying to say, the words just come out perfectly. Unfortunately, we believe we're responsible for all our actions/thoughts (ego-identification) and sabotage ourselves with too much thinking and worrying.
Sometimes we just gotta get out of our own way