motivationLeverett, T. (2012). Review of Motivation and Second Language Acquisition: The Socio-Educational Model, by R. C. Gardner, TESL-EJ (TESL Electronic Journal), 16, 2, Sept.
This is an interesting review because this researcher is clearly tired of the general public's misuse or misunderstanding of what he calls "motivation". Motivation to him is not a reason to do things, but rather, only the juice you can successfully convert that reason into. So that, if have a good reason to study English for example, but you don't enjoy your classes, you cannot truly be called motivated, since you haven't converted your reason to a useful kind of energy.
Now this language of "converting" is entirely mine, but Gardner's point remains: motivation has to be measurable, and measurable in terms of what you do and feel in the activities that you are "motivated" to do, and just having a reason isn't worth much, since everyone has a reason. For example, everyone has a good reason to exercise, but only a few of us actually do it. So the reason isn't a "motivation." The "motivation" is measurable in that if I really want it, I will do it, report getting something out of it, and enjoy it.
Ah but you can't change the words people use, or what they mean by them, unless you have an extensive campaign or unless, by chance, thousands of people read your book and act according to your wishes. Well, this is a good start, maybe.