Why does WaniKani teach the on reading for the kanji character 崖, when its only used in one vocab word (namely 崖), where the kun reading is used?
A search in jisho also indicates the on reading isn’t used in any common words, it seems a bit pointless to me to teach the on reading for this character.
Although you can try suggesting, I wouldn’t put much hope in it. Only that it is certain for me that many many Kanji in Wanikani need to be re-encountered somewhere else, hoping that memory from Wanikani would help, falling out of expectation sometimes, and eventually learning more of the Kanji.
Half of it is also the inferring skill, so taking the On reading from Kanji looking similar to 崖. Otherwise, hearing the vocabulary first, and seeing the written form later.