The motivating factor that is satisfied by Joe's boss in his request is: People.
Motivating in the business sphere refers to the factors that can push people to achieve more.
In the case of Joe described above, we find that his boss gives him tasks that challenge his abilities. If he meets up with the challenge, he feels a sense of satisfaction and fulfillment.
So, the motivating factor that is satisfied is people.
Learn more about motivating factors here:
https://brainly.com/question/1520697