Hi,
Why, in Anki deck settings, can I directly control the interval for “Again”, but not explicitly set the intervals for “Hard,” “Good,” and “Easy”?
Because Anki is a spaced repetition app, where intervals are supposed to get longer and longer the more you press any of those three buttons.
You can actually leave the relearning steps empty and Anki will decide the “Again” interval. Though, this isn’t recommended as of FSRS 6.
Scheduling cards is Anki’s job. You don’t need to directly control the intervals.
actually there’s an option(desired retention).
That doesn’t allow you to “explicitly set the intervals” – which is what you asked for. But yes, that’s the way to overall set your calculated intervals to be shorter or longer than they currently are.