Somebody can correct me if I'm wrong, but an audio CD recorded to a CD-R has a finite lifespan. Commercial, "stamped" CD's aren't nearly as prone to degrade. You need to have backup files of your work.
If you burn a data CD with .wav files on it, there's some degree of protection from having parity data included that can calculate and reconstruct missing data if and when (more than likely, when) the media becomes slightly corrupted. A data CD will not play in a normal CD player, and an audio CD-R doesn't have the parity data. As far as optical media, CD-R's are about the worst for degradation. DVD-R is a little better. An optical hard disk or SSD would be better for longer term storage, but might still be prone to failure.
If you have a CD-R that works well for up to 5 years, that's good.
Gotta have backups.