What are the reasons for failure of digital millenium act ?

The Digital Millennium Copyright Act (DMCA) is a United States copyright law that implements two 1996 treaties of the World Intellectual Property Organization (WIPO). It criminalizes production and dissemination of technology, devices, or services intended to circumvent measures (commonly known as Digital Rights Management or DRM) that control access to copyrighted works. It also criminalizes the act of circumventing an access control, whether or not there is actual infringement of copyright itself.

For in depth analysis of DMCA read the document below :
http://en.oboulo.com/failures-of-the-digital-millennium-copyright-act-and-its-threat-64988.html