Slow Learning
If you try to learn something too quickly, you won’t learn it at all. Learning requires a degree of slowness, so it cannot be directly optimized. It may take X number of days for your brain to fully grasp a subject, and while some interventions like improving your study habits might help, there will be a minimum amount of time required for you to learn. This was a very difficult realization for me, but I think being aware of it helps immensely with time management. If I tried to cram in some new knowledge in X-1 days, I would prevent myself from deeply grasping the material and my understanding would be limited. So spending that extra day is actually the right choice in order to maximize the effectiveness of time spent learning.