A motive is “something (such as a need or desire) that causes a person to act.”
So, to ‘motivate’ is to get someone to act by creating a need or supplying a desire to do so.
When working with a group, maybe the question shouldn’t be how to motivate people, maybe the question is how to find the people who come with the motive that is aligned with what you seek?
And if our thinking mind wants to act a certain way, but the emotional mind is getting in the way, how can we align the two? Gretchen Rubin’s four tendencies may be an interesting place to start.