Sometimes people misinterpret a manufacturer's claims by making a lot of assumptions based on buzz words. Heise Security shows how that exact scenario is possible when choosing an encrypting hard drive.
When you read the story you'll find that even though a certain manufacturer spoke of "128-bit AES encryption" it turns out that the actual encryption being used to "protect" data was not AES, and the encryption that was being used incredibly easy to crack. As a result all of the data on the drive become openly accessible. Ouch.