Some consumers are finding that older CD’s in their collection are degrading, suffering from “CD rot,” a gradual deterioration of the data-carrying layer. It’s not known for sure how common the blight is, but it’s just one of a number of reasons that optical discs, including DVDs, may be a lot less long-lived than first thought. ‘We were all told that CDs were well-nigh indestructible when they were introduced in the mid-’80s. Companies used that in part to justify the higher price of CDs as well.”