I'm going to assume that you intended to list "intensity" instead of "definition" as the third key element of motivation, ranger 1980.
Persistence deals with the dedication one brings to the completion of a task. One might be motivated to stick with a project for a variety of reasons, such as enjoyment of the task, feeling challenged to conquer the work, curiosity to learn about the end result, fear of failure or threat of penalty if the work is not completed, desire for reinforcement that occurs as long as the work continues,...
Direction, as noted above, refers to choice. When a person is presented several options, one chooses one particular possibility to follow because, for whatever reason(s), that option is most appealing to the person. Direction reflects that choice of alternatives and the activity that follows the choice. One usually chooses the option that is the most highly motivating and therefore the most likely to be fulfilled or completed.
Intensity deals with the depth of involvement in the work being done. A person who is highly motivated by a task may choose to spend much more time and effort working on the project than is expected or required, devoting much intense thought and concentration upon the task. A person who is not intensely motivated may complete the task, but not display any enthusiasm and certainly not with any extra effort put forth.
In terms of organizational behavior, the leader of an organization raises the level of involvement and cooperation of the followers in the group as the followers increase involvement and buy-in regarding the direction. As commitment to the project is supported and positive outcomes are explained, the leader should be able to raise the levels of persistence in finishing the work and intensity in doing it well.