What factors make one prioritize a task higher another ones? What are some models about it?
Note that I'm not asking what makes one wants to do a thing. That's motivation, and there are plenty of models behind it. Here I presume the subject already has motivation to do a task, and I just want to examine when they will do that task, given there are other motivated tasks alongside.
The Eisenhower matrix is a good start, as it indicates two factors: importance and urgency. However, I think there are more to this.