For some types of content, DRM can be a great solution because it is typically secure. For example, downloadable content is generally a good fit for DRM solutions and for all practical purposes the only way to secure a media file that’s been downloaded to an end-user’s computer.
However, most content providers avoid DRM solutions for the following reasons:
Labor Intensive
Your media content will generally need to be re-encoded to include DRM information.
Limiting
DRM is really designed for progressive download applications, not for true streaming. Some DRM solutions require that you use proprietary encoding formats for your content. Often, content can only be played using the DRM vendor's proprietary player.
Expensive
Most DRM solutions require very expensive server licenses and/or service contracts, often approaching tens of thousands of dollars. Some DRM solutions also require special hardware.
Traditionally, DRM has been the preferred method of content delivery for end-user devices (phones, media players, etc.) due to their “disconnected” nature. This has changed. Wireless internet connectivity is now ubiquitous, as is streaming media support on most next generation devices.
This means that consumers will grow increasingly dissatisfied with long downloads and limiting DRM schemes (that often inadvertently punish legitimate users). Instead, consumers continue to raise their expectations regarding user-experience and desire for instant access to content.