Desire: How motivated are you? It's 80% WHY, & only 20% how! Found out the why!
Deadline: For time perspective, and 'pressure'. Has to be realistic, ie. a time frame you genuinely believe is achieveable for each mini-step you have to take towards accomplishing your goal.
Discipline: Discipline to take action and stick to your deadlines. I believe the self-help industry is so huge and is going to remain huge, until people start taking action. If you actually took action you'd stop needing to go back to the bookstore so often to buy even more information, on exactly the same topic, that you're not going to do anything with anyway.