New artists often just want people to hear their music, so they can build a following.

There are millions of people who want to sift through new music to find the next gem.

How can it be so hard to build a platform where these kinds of demand and supply meet?

There is a separate, market where established artists want to monetise mainstream listeners, and I can see that's what iTunes etc provide.

Maybe I'm overestimating the size of the 'sifting' market, because I'm one of those people?