A key part of learning is being able to admit where you've gone wrong in order to fix it. Argyris (1991) used the example of the manager asking his subordinates to say where they could improve is the type of single loop learning that I was frequently engaged in before I took this course. Doing the weekly reflections each week teaches us to get better at examining where we went wrong and what we could do better, effectively teaching us double loop learning.
Argyris, C. (1991). Teaching smart people how to learn. Reflections, 4(2), 4--15