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The Science of Motivating Others

Motivation equals expectancy plus value minus cost.

Key points

  • Research suggests motivation is the product of high expectancy, high value, and low cost.
  • Systematically determining the source of motivational problems makes motivational interventions more likely to work.

How do we motivate those under our care to do what’s in their best interest? This is a question many of us—who are supervisors, parents, teachers, coaches, or other kinds of care providers— regularly ask ourselves. Often individuals could do so much if they could just find the needed motivation.

Jeswin Thomas | Unsplash
Source: Jeswin Thomas | Unsplash

For example, I teach psychology courses to first and second-year college students at a large, diverse community college. Although I suspect many of my students have the potential to thrive in school and in their future professional lives, a substantial number fail to follow through with their intended plans. At the classroom level, many don’t attend class, complete their homework, or study sufficiently well for exams. As a result, their grades suffer, and many withdraw.

Beginning with my involvement in an intrinsic motivation research lab at the University of Wisconsin about 30 years ago, and later continuing with my dissertation research on goals at the University of Minnesota, I’ve long been fascinated by the science of motivation. As some scholars have recently described, much of what is known about motivation can be summarized in the following way:

M = E + V – C

In this “equation,” motivation can be seen to result from the interplay among three variables. “E” refers to expectancy, the belief that you can do a behavior and achieve a result. My students display high expectancy when they believe they can learn psychology, can complete assignments effectively, or can perform well in my course. “V” concerns value, the perception that a task is rewarding or useful. My students reveal high value when they find class activities to be sincerely interesting or connect what they’re doing in my course with an outcome they later want, such as being able to get a job or do that job well. “C” relates to cost, the sense what you’re doing causes some kind of pain. My students express high cost when they report frustration over reading long chapters or find the amount of time needed to do well in my course interferes with other life priorities.

Oftentimes, when we try to motivate others, we automatically defer to one element of the equation. Some of us prefer to inspire people by encouraging them to believe they can succeed (expectancy). Others of us would rather highlight the enjoyment or secondary gain that comes from an activity (value). Still others of us favor removing barriers to engaging in a task (cost).

As the pioneering motivation psychologist Abraham Maslow once put it: “If the only tool you have is a hammer, you tend to see every problem as a nail.”

I surely have been guilty of this mistake in my teaching, at times. Maybe because of my background in intrinsic motivation, I focus much of my efforts on stimulating students’ “knowledge emotions.” When a class seems to be underperforming, for example, I typically assume it boils down to a lack of perceived value in what we’re doing (the nail), and thus I redouble my efforts to catch and hold students’ interest, evoke surprise, or stimulate awe (my hammer).

Although low perceived value could be a problem, this tendency of mine overlooks the possibility there may be other sources of difficulty as well, such as low expectancy or high cost. If low expectancy was the main problem, an intervention designed to change students’ mindsets away from a belief in fixed ability toward a belief that ability can be grown through hard work, persistence, or the use of new strategies may be more effective. If perceived cost was the main problem, an intervention focused on addressing that at an individual or systemic level may be more appropriate. (In fact, some findings are starting to emerge suggesting that cost, in particular, may often be the most common motivational stumbling block for individuals from marginalized groups.)

Supervisors, teachers, parents, coaches, and other kinds of care professionals often try hard to help others do what’s in their best interest. However, as Maslow suggested, we sometimes can be ineffective when we’re applying the wrong tool. We would do well to expand our toolkit to see if a different tool might produce different results.

To start, we can pay attention to whether motivational problems in a particular context are due to low expectancy, low value, or high cost. This could even be systematically assessed. Once we determine the most significant sources of motivational struggle in those we are trying to help, we then can be more intentional about selecting the best tool to match the problem at hand.


Barron, K. E., & Hulleman, C. S. (2015). Expectancy-value-cost model of motivation. In Wright, J. D. (Ed.), International Encyclopedia of the Social & Behavioral Sciences (2nd Edition) (pp. 503-509). Elsevier.