Spaced repetition memory systems make memory a choice, but it requires that people adopt a regular memory practice habit. And adopting any new regular habit is a burden for most people. But most people find this to be a fairly unpleasant habit: rote review of flashcards, which may remind one of high school.
So a successful Spaced repetition memory system must deliver significant personal value immediately to overcome this barrier to adoption. Most systems don’t: they’re an empty box meant for the user to fill. But Writing good spaced repetition memory prompts is hard, so most users’ initial review sessions will comprise a small number of mediocre prompts. And Spaced repetition memory systems don’t rapidly demonstrate their benefits. So people churn.
We often meet people who say “Oh, I thought spaced repetition sounded great, and I tried Anki etc, but it doesn’t work for me”. Dig down a little, and it turns out the person is using their memory system in a way guaranteed to fail. They’ll be writing terrible questions, or using it to learn a subject they don’t care about, or making some other error. They’re a little like a person who thinks “learning the guitar sounds great”, picks it up for half an hour, and then puts it down, saying that they sound terrible and therefore it’s a bad instrument. Of course, what’s really going on is that the guitar and memory systems are both skills that take time to develop.
(Matuschak and Nielsen, 2019)
Matuschak, A., & Nielsen, M. (2019, October). How can we develop transformative tools for thought? https://numinous.productions/ttft
O’Day, G. M. (2022). Ending on a high note: A simple technique for encouraging students to practice retrieval \[Unpublished doctoral thesis, Purdue University\]\ found improved attitudes to retrieval practice by appending easy questions at the end of a practice session.