There are a few big issues, but the easiest one to fix is the reset interval.
When you forget a word that you're reviewing (that is, when you hit "Again"), anki resets the interval to 0%, as if it were a totally new card.
This is bad for 2 reasons. 1) A lapse is not the same as learning a completely new word. When you review a lapsed card you're just refreshing that connection that you've already made. So it's wasteful to completely reset the interval unless you've really totally forgotten the word.
2) The interval reset can be huge (going from 7 months to 1 day) so it makes it tempting to just hit "Hard" instead. I know I've done that.
The fix here is to set a more reasonable reset value like 40-60%. I use 45%.
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The other big issue is the algorithm works differently than you would expect. I discuss this in more detail in my post, but essentially anki gives each card a modifier value. Starting at 250%. Every time you hit Again/Hard/Easy, it -- permanently -- modifies this card. This is quite unintuitive! When people grade a card, they're really grading their own memory / ability to recall. Not how hard the card itself is.
Why is this bad? Because if you hit "Hard" a lot, then you're seriously capping the interval growth rate for a word. In other words you'll see it way more often than you need to. Most people don't hit "hard", -then- "easy" once they learn it. A lot of people I know hit "hard" to be on the safe side instead of "good", purely out of habit. This picture explains why a low modifier is bad. [1]
The way I fix this is by using 2 plugins: the first makes grading buttons not modify a card's modifier, and the second one resets ALL cards to 250%. Low-Key anki goes over this in detail. [2]
However! This fix assumes a relatively homogeneous deck in terms of card difficulty. I.e. words for a language. If you're studying, say, algorithms or something where the difficulty may be heterogeneous, then you may want anki's default behavior.
[0]: https://andrewzah.com/posts/better-anki-usage-guide-2019/
[1]: https://s3.amazonaws.com/andrewzah.com/posts/017/ease-exampl...
[2]: https://massimmersionapproach.com/table-of-contents/anki/low...
I have been using Anki for Chinese with a premade deck (Spoonfed Chinese, if anyone is curious) for around 1.5 years and reviewing time has crept up too much. I have lowered the number of new cards per day several times (started at 20, now at 12, thinking about going to 10) but I am very averse to change the rest of the defaults since they are very technical things and it's hard for a layperson to know the optimal settings. I trust the Anki devs to have more data on, e.g., the typical rate at which we forget things than I, a random language learner, can have; what do I know about that? So I fear that changing something may harm my learning (currently I get more work than I would like, but I do learn).
You seem to know what you're talking about so I'll try your advice (thanks a lot for it!). But if any Anki dev is reading, please, pay attention to the defaults. I'm sure the overwhelming majority of users are going to use them, out of lack of information and/or fear of tweaking things that we don't know much about. It's a pity to have such an awesome software not live up to its potential due to bad defaults.
Would it be hard to ask the user a small questionnaire, like "how long are you planning to study this subject?", "do you have a specific goal (learning X cards by date Y)?" and "what is the average and maximum time you are willing to devote per day?", and use that to set reasonable options for that user?
IIRC the anki defaults seem to be geared more for short term, dense studying (like for tests). In those situations you would want a lapse to reset the interval to 0.
For longer term learning, you ideally want an 80-90% recall rate. [0] In my post on anki I have two studies that look at the effects of longer intervals on learning. [1]
[0]: https://eshapard.github.io/anki/target-an-80-90-percent-succ...
[1]: https://andrewzah.com/posts/better-anki-usage-guide-2019/#re...
If you hit "hard" on a card, and then months later it re-appears, at which point you now remember it well and hit "good", doesn't it reset the state of that card back to normal?
This is why people who use Anki long term recommend not hitting the Easy button: it’s a permanent +15% modifier.
This algorithm -does- show you certain cards sooner or later but it does it in a nonintuitive way.
Cards marked “Hard” like this will end up being seen way too often. This picture (1) explains the problem.
(1): https://s3.amazonaws.com/andrewzah.com/posts/017/ease-exampl...
Everybody I would urge you to read this comment if you are an Anki user.
The point about Anki is not the sw but the intervals and if you haven't got them right, there's not much point.
I think there's also a setting to limit new cards based on review size, and that also helps avoid review hell. I imagine it's not the default because a popular use case is students in courses where there are high stakes deadlines.