A career as a musician requires two things: music to play, and people to listen. Everything else in a music career relates to those two things.
As a musician, it is crucial to find a way to get your music in front of people. Radio is no longer the primary way for people to hear new music, and for younger fans, radio barely registers at all. An online presence for your music is a must.
First, selling music online is the best way to ensure sales. People buy almost everything online, and music is only available online in more and more places, so without online sales you will miss the opportunity to ever sell anything, as there will be no other way for people to buy your music.
Second, the artist must have music available in a music player online so that new fans can share their discovery with their friends. People love to share musical discoveries with others, and that means musicians must give fans a way to do that. If fans can’t send a link to their friends, or post to a link on their favorite social network, the potential new fan won’t even mention your music. The listener will simply go on to the next discovery they make that does have a way to share music online.
Selling music online is easy. The more places it is for sale the better, both because it will increase the musician’s overall search engine presence, but also because the music will be more likely to show up in front of someone who is inclined to like the music.
And when a new fan finds and likes your music, make sure that person can tell other potential fans about it by having a music player online for them to share it with.