Comment by jhogendorn

Spotify is pretty notorious for having built a custom shuffle algorithm, ostensibly to avoid random turning up things humans perceive as non random, like playing songs by the same artist a few times in a row. But their implementation has always been bad, it seems they maintain an internal 'shuffled' playlist they generate once, so while on shuffle you hear the same songs, in the same order, typically from the top of that hidden playlist, so you only every get the first N etc. Theres also rumours that people have noticed shuffle gets biased according to profit motives. Either way, shuffle on spotify has for a long time been a joke. There used to be tools that would mess with the playlists in just the right ways to get it to redo the hidden shuffled playlist.