There are (at least) three levels of priority. Let’s call them Life Goal Level Priority, Project Level Priority, and Action Level Priority.
Project Level Priority
Projects are all the todos that don’t fit in a single sitting. I’m taking the name from GTD’s projects. In a project, you have to ask someone else to do some work and remember that they’re working on it so that you can follow up.
Another project might be work you can start but know you won’t finish in one sitting, so you need to manage the task of continuing the work.
A third project might have multiple parts. Making fish sticks involves putting them in the oven. At that point, you have some free time to do something else, but you need to schedule yourself to pull them back out of the oven. Most people use a kitchen timer, but the concept of following up after delegating is quite similar.
Our projects and their priorities will set the priority of actions, what meetings we attend, and what emails we send.
The Goal Level Priorities set the project priorities.