“Ping failed because Apple didn’t make it easy enough to share the music users truly care about–rather than simply receipts for the songs they purchased. Others in the space have avoided such stumbles–it’s arguably the reason why Spotify has become so popular and why Google wanted to enable full-song sharing on Google+. ‘We have to make sure that if I want to share a song with you, that you can listen to that song whether or not you’re a Rhapsody subscriber,’ Irwin says.”