I’ve come to see it as part of the design. The system is making sure not only that you remember it, but that you haven’t confused it with any new information (like 子 and 了 or 大 犬 and 太). If I really don’t know it, I deserve to see it more frequently.
I use the Self-Study Quiz scripts judiciously to review things I’ve missed recently, missed often (called leeches), or to review readings I’ve jumbled for things like 人, 生, 日 or whatever.
I agree, that first Guru level can be like, wow, I’ve never seen this symbol before in my life! Or, I’ve seen it, and I know for sure the reading I’m typing in there is wrong.
A few weeks back, I started using KaniWani when I have the time and energy for it, and I’m behind enough that it helps jog my memory a bit on stuff that’s older. It’s an English to Japanese for vocabulary only, and will really make you suffer with verbs and words with similar meanings.