The best motivation is self motivation, but the strongest motivation can be from either self or from someone else.

Nothing beats the motivation you give yourself, even though it may not be the strongest in every case, it is important that everyone is able to motivate themselves by themselves. If you depend on other people to motivate you, there will be times when they will not be there and you will need motivation. And because you depend on someone else's motivation always, you will find it hard to do what needs to be done sometimes. When you can self motivate yourself everytime, you will be able to say to yourself everyday the things you need to hear and will always have the motivation that is needed to do what needs to be done.