Comment by accrual
Yes, good distinction. Recordable media will most likely contain data an individual intended to save. But because it's recordable, the dyes and structures on the disc aren't as stable.
Long-lasting, good quality mastered optical media is probably mass produced and has many copies, including a distinct and potentially well-preserved source.
It's probably fair to say that a lot of mixtapes (mix CDs?) from the early 2000s are lost to dye issues...
> lost to dye issues...
Not that it helps to recover older data, but things are better with Blu-ray today; at least if you buy decent quality discs. Advertised lifespans are multiple decades, up to 100 years, or even 500 years for "M" discs. And in the "M" disc case, it's achieved by using a non-organic dye, to avoid the degradation issues.