Below a short list of activities that explain, in my opinion, the concept of priority.

Important and urgent
Last-minute assignement from your boss and impediments.
Impediments are all things that slow down productivity or block team activity.

Important and not urgent
These are important activities that can be managed and scheduled to be performed at the right time.
It is not the place for improvisation.
For example, coaching and planning are two activities that are much important but not urgent.

Not important and urgent
These are activities that you can delegate quickly.

Not important and not urgent
Don't waste your time in these activities.
For example unimportant phone calls.