Support is external. There is a difference between the two, but most people use them interchangeably. I can not seriously motivate anyone on a long term basis, but I can encourage and support them. Likewise, only I have the power and motivation to change myself. Of course, this is only my opinion.
Using "motivational' posters and quotes only works if they parrot your motivation for improving fitness. These pics illustrate my motivation levels and focus this week:
(OOPS! Pics to be added when I get to my own computer; at work now!)