The Internet has created a multitude of outlets to discover music from across a wide variety of regions and styles. It's become more and more difficult to process what's released, and as a result, songs with the potential to become bigger or even major hits can end up on the wayside while labels push whatever artists have Tumblr buzz or well-connected management.
But a great song is a great song, and 2012 had a surplus. Some of these are tracks from established artists who've been discounted or had off-years; some are from rising stars who could be much bigger in 2013. Many are artists who've had some regional fame, but lack the connections to attract the attention of radio programmers and industry.
The one thing all the songs have in common is that they should have gotten more attention, were there some justice in the world.