Because, as I said above, it's a very complex problem :)
I honestly don't know much about recommendations (and what I know I probably cannot tell). But there's definitely continuous work done on them. But it can also be hampered by extremely conflicting requirements (where "some" both means double-digit procent of users and these "some"s overlap with each other):
- some users want more of the same, some users want a more diverse listening experience. Some of these users are the same user, but on different days
- some users mostly prefer curated suggestions, some users want ranodm stuff. They can also be the same user :)
- some users a heavily weigted to only a few artists, some users listen to evereything and anything. And even this can be the same user :)
- there's probably stuff about licensing, availability, contracts etc. at play as well, because in streaming services it's always there, in very bizarre ways
Basically every single tweak to recommendations will break them. And yeah, Spotify employees will complain about this more than anyone else, all the time :)
I honestly don't know much about recommendations (and what I know I probably cannot tell). But there's definitely continuous work done on them. But it can also be hampered by extremely conflicting requirements (where "some" both means double-digit procent of users and these "some"s overlap with each other):
- some users want more of the same, some users want a more diverse listening experience. Some of these users are the same user, but on different days
- some users mostly prefer curated suggestions, some users want ranodm stuff. They can also be the same user :)
- some users a heavily weigted to only a few artists, some users listen to evereything and anything. And even this can be the same user :)
- there's probably stuff about licensing, availability, contracts etc. at play as well, because in streaming services it's always there, in very bizarre ways
Basically every single tweak to recommendations will break them. And yeah, Spotify employees will complain about this more than anyone else, all the time :)