The idea
Four marks and one decision
A teacher writes down four scores: 72, 65, 48, 85.
On their own they are just numbers. Average them and you get 67.5. Notice that one student is below the pass mark of 50 and you have understood something. Decide to run remedial classes for that student and you have acted.
That climb, from numbers to a decision, is the whole subject in one slide.