I forget where I read the story (might have been Cryptonomicon), and I don't know if it's true, but I find it quite illustrative of the point.
During WWII the British where finding that some of their messages encrypted with one time pads where being cracked by the Germans. Since they where pretty sure that was mathematically impossible they where quite shocked and immediately launched a full investigation.
Eventually they found that the problem was the team generating the one time pads (basically a room full of people drawing bingo balls with letters on them at random) had started second-guessing the randomness of letters generated. They'd started to subconsciously avoid balls that would lead to what they thought where patterns in an attempt to make the otp more random. Of course this lead to less randomness and broke the security of the otp.
Encryption deals with sending messages from A to B such that a third-party C can't intercept the message. In a DRM scheme B and C are the same, which is why DRM is flawed by design, because:
(1) no amount of patching can ever fix it
(2) it punishes legitimate customers, as pirated content is far easier to deal with, while not suffering from lock-in effects; the irony might be that DRM is helping the prevalence of piracy
(3) no matter how hard it gets to create the initial DRM-free copy, from then on all other copies are zero-cost - which means it only takes one dedicated individual to create a pirated copy and all people that pirate stuff can enjoy it ;-)
> DRM has a purpose
Of course it does. Its purpose is to save a dying business model that was made obsolete by technology ... 1000 years ago there were businesses selling ice to clients.
The equivalent of DRM would have been to restrict refrigerators from producing ice. Fortunately for us, we realized that selling refrigerators is a lucrative business too.