No it doesn't. As a child, one time I tried to make a CD unplayable and literally couldn't do it. (Sandpaper didn't do the trick.)
The real issue was the skipping when you tried to use a portable CD player.
Yes it does.
> As a child, one time I tried to make a CD unplayable and literally couldn't do it. (Sandpaper didn't do the trick.)
Either child you was incompetent or your player was very good at error recovery, because I personally saw a number of car CDs thrown out as the car’s stereo was unable to read them anymore.
If it did exist, some toothpaste rubbed tangentially around the CD on your fingertips was often enough to buff it out, at least as far as the 30-byte limit cared.
It was a phenomenal jump in data integrity, built in at the recording level. Sure, you could encode even floppies with that scheme... but your computer didn't, natively.
But the label side is indeed very fragile as you can easily damage the reflective pits, only covered by a layer of paint. It's as same as a simple mirror, where the thin layer of reflective metal is very well protected from the front but is only covered with paint in the back.