DRM, in most circumstances, ultimately serves no purpose beyond reducing the value of the product while increasing the value of the illegally obtained alternative. The more restrictive DRM is, the greater the extent to which it could be considered a implicit encouragement for illegal activity. It's not complicated. A DRM-protected music file is locked into a specific format and can only be played on one device, which is often required to be of a specific brand. An illegally downloaded song can be converted into whatever format is most convenient and played on any device the consumer happens to own. Even without considering the money saved, music piracy is still a vastly superior option to legitimate purchases. The situation is even worse with computer games, the DRM attachments for which often behave in ways completely indistinguishable from malware.
FTC Town Hall to Address Digital Rights Management Technologies - Event Takes Place Wednesday, March 25, 2009, in Seattle #539814-00170
FTC Town Hall to Address Digital Rights Management Technologies - Event Takes Place Wednesday, March 25, 2009, in Seattle