Equally good scientific polling, along with the best available social science, can t deliver the election to both of the two main presidential candidates, current indications to the contrary notwithstanding. One will lose, despite everything. Two rival car dealers in the same town can read the same book on success, and, in principle, do exactly the same things as a result. Both cannot possibly be number one. Some ventures succeed and others don't.
Some successes are outrageous, and others are quite modest.
Fortune may smile on you today and pull the rug out from under you tomorrow. Human beings have free will, and the responses of other people to what we do can never be completely guaranteed. The individuals we most want to please or motivate may embrace our projects, or reject them, despite our best efforts to the contrary. No principles or guidelines of success describe absolute necessities. Because of that, there are no complete and reliable guarantees that if you do certain things, a specific result will unalterably happen out in the world.