It seems like the core things that Anki needs are new user experience improvements, and algorithm updates. SM2 really shows its age as compared to other algorithms.
For me really learning a word means:
(1) Knowing how to say it.
(2) Knowing how to write it, meaning the Chinese characters, of course.
(3) Still remembering (1) and (2) after at least a month.
(4) Being able to actually use the word correctly.
Do you really learn 20 words properly under those definitions? If so, then respect. I consider myself to have quite a good memory for visual information, but if I don't try to memorize 20 words as a full-time activity on that day, and write them hundreds of times, I am fairly sure they won't stick for long, maybe not even until the next day. Some obviously will, and some have good explanations why the characters look as they do, but others don't, and feel arbitrarily constructed.You learn the words for a day (you're able to match the sounds and meaning to it). You will forget a lot of them tomorrow, so now you have to re-learn them. This is just how Anki works. You keep learning and re-learning until they stick for a prolonged period of time. It's common for Japanese learners to add between 20 or 30 words to their learning queue.
If you understand how Anki works, you will also understand how the word learning is used in relation to its flashcard mechanism.
And with all due respect, someone claiming they learn 20 words per day, in Mandarin, is an almost outrageous claim. If you think that "learning" is commonly agreed upon to mean "memorize for a couple of hours", then please show me the research into the meaning of the word, that proves your claim. While I have explicitly stated, what _my personal_ definition is, you are claiming to be knowledgeable about a "commonly agreed upon" definition. That is an impressive claim in itself. Let us all hear that definition, that is so commonly agreed upon, so that we can gain from that.
What you call learning, I call "training" or "practicing" or "revising". Now the onus is on you to prove to me, that indeed as you claim there is some commonly agreed upon definition, specifically in the area of learning Mandarin, that proves, that my definition is off.
And I will have you know, that I am learning Mandarin for some 10+ years, and have a lot of experience in that area. I know what counts and what is important.
When people in the language learning community say they "learn 20 words a day", they are referring to New Cards Added. It is a metric of input and initial encoding, not guaranteed permanent storage.
In Anki, "Learning" is literally a specific phase (the red cards). You introduce the card, you pass the initial threshold, and then the algorithm handles the retention over the subsequent weeks. You are conflating the process of learning (adding new information) with the result of mastery (long-term active recall).