[ThirdFoundation]

To add to your point, I think this reinforces the value of spaced repetition learning. It's been show to been one of the best ways to actually retain information. So, as you said, just doing the exercises only gets one so far. You'll need to either use what you learned or at least do refresher exercises to better put what you learned into memory. The benefit is that you may be able to do these refreshers and greater intervals over time, effectively retaining the information longer.

For me personally, there does seem to be a tipping point where what I learned really sticks in my brain and degrades much slower. However, I can't seem to pinpoint where that point happens or if it is even consistent. There are some coding concepts I never forget, and some that seem to leave me within a month.

https://en.wikipedia.org/wiki/Spaced_repetition

https://eric.ed.gov/?id=ED427772

https://www.theguardian.com/education/2016/jan/23/spaced-rep...