I use it (Anki), but this is the 3rd time I got started using it (I dropped off twice).
For me, personally, these are the reasons:
- It was kind of annoying to do Anki every day at first. Cards always seemed either blindingly obvious (and seemingly a waste of time), or I just didn't know the content (in which case, it was frustrating knowing I'd have to memorize it right there since I knew it'd pop up again in a few cards). Not knowing the content tended to be caused by having too much info on the Anki card.
- I didn't see the benefit clearly until after a few weeks of doing it, when stuff EVENTUALLY sunk in.
- About 70% of the time, I discovered that the card I created was inadequate in some way.
* Some I just deleted because they were discovered to be redundant (i.e. covered by another card)
* Some I discovered to have to much info (so I had to break it into more cards)
* Some were just awkwardly phrased
* Some were good cards but displayed weirdly in the Anki mobile app.
I'd say the #1 thing that kept me from fully adopting it:
Not making cards as atomized as possible made things a pain.
I was lazy and made cards contain more info with the justification that I needed to see everything at once in context. This resulted in bloated cards and frustration.
Trust me: Every card should contain one idea. It will result in you making tons of cards, but it will make your daily Anki a lot less frustrating (and you'll be more likely to do it).