I think changes in a person's music taste depends on who they are mostly. Age might be a factor, but not for everyone. I personally feel there's no way I'll grow out of Jmusic, even if my mum foresees it, aha. My taste in music has been mainly Jmusic for a good few years now ever since I found it after thinking the only music out there was the mainstream pop you see on MTV and such. I still enjoy the music I used to listen to at times. I've never done a full 180° turn, music wise, just language wise I no longer look into anything English and just Asian. It's more like the more I discover/am shown to, the more I get into everything else. I've never been able to move past something I once enjoyed. Yes, even Mr Bieber. Music lovers who suddenly move on from their first love or such might be having a moment in their own life and need a new distraction. Or they might've found something else they believe is a step up. Or because the band has changed, they want to forget they were even ever a thing and find something else to latch their attention onto. It's very startling to see such a thing happen, but even so, it's quite interesting.