In 2012, Google executives were reported to be upset with the lack of interest in Google Music, and particularly dismayed its inability to bring in revenue. One aspect that hurt its adoption was the lack of a mobile app for iOS.
That means Google Music is a lot like Google Wallet: years ahead of Apple, but so poorly planned and implemented that it completely squandered its vast head start.
Google apparently expected its paid on-demand streaming music service to be quite popular among Android users, but instead got a taste of what its Android developers had already been eating: the platform does not attract people who want to pay for things, particularly not anything that can be pirated. Google Music mostly demonstrated the weakness of Android as a platform for supporting commercial apps and services.
On the other hand, these users are willing to sit through ads to use the services for free.