From my experience, commercial CD/DVD seem to have way higher quality and longevity than your personal CD-R/W etc.
I've purchased lots of 80s second-hand CDs that often have awful case conditions and they all read totally fine (as in, the CRC32 checks out with online database).
Is there a reason for that? Do they simply use better material or they have better tech to write them?
Yes, the processes are very different. Commercial discs have physical pits pressed in the recording layer, while burned disks just use the laser to change the reflexity of the layer (which is some dye or phase changing alloy).
I've purchased lots of 80s second-hand CDs that often have awful case conditions and they all read totally fine (as in, the CRC32 checks out with online database).
Is there a reason for that? Do they simply use better material or they have better tech to write them?