"broadening their musical horizons?
I'm not even sure what that means..."

eg I got into bluegrass and country through playing fiddle with a bunch of friends who were into it. this led me into old-time music, which in turn got me into English folk music, because they had shared roots. I then got massively into the blues (which I'd always thought was boring simplistic old man's music when I was young and foolish). Then I checked out African music, starting with Malian kora and guitar stuff, which made a lot of sense to me, because it sounded very bluesy. Then neighbouring African musics (like Congolese rumba and stuff). Once you get into North African music, then that gives you an insight into the music of the Middle East. etc etc

One thing leads to another. In each case I'm not sure I could have enjoyed that particular type of music if I hadn't already got used to the one before.

If I had started editing a music magazine 20 years ago, it would have been indie, punk and hip-hop-based. If I'd carried on editing a music magazine, and it had continued to reflect my tastes, it'd be very different now to then.

that's what I meant by broadening one's musical horizons.