I look at my own music tastes as roughly two levels. One level is whether I objectively like the music. The other level is what I'm in the mood to listen to. I can definitely not be in the mood to listen to some music I really enjoy. But there is also music I will never enjoy no matter the mood. I don't think a recommendation system will work very well if it conflates those two levels.
Wouldn't it be nice to have recommendations that effectively address both levels and understanding not just your general preferences but also your current emotional state
