Self motivation is like the foundations of a house. Whenever you try to achieve something in your life or personal projects, you must have a strong self motivation beacuse when bad times come (and eventually they will come) your project will collapse if you are not self motivated. It works like a shield against troubles and hurdles. Of course, it is complicated to be self motivated all the time, but I am sure that one of the differences between succesful people and those who are not is that they keep self motivated in spite of the difficulties that they have.