I figured my layman explanation would suffice. While we're in the realm of correct details, it's also worth nothing that with each use of a needle dragged through a groove (or even with magnetic tape dragging across all the bits in the tape machine) the surface is degraded and the original recording along with it. Less fidelity, more noise ... hiss, pop, crack

Digital gives us error correction so that even when the physical media starts to degrade (taking the signal with it) our firmware and our software work out where the mistakes exist and attempt to correct them. Of course, once the signal has degraded beyond the point of recoverability, you "suddenly" have a catastrophic failure. (And this is why backups are important...)