VERY GOOD
Disc looks like it was viewed only once. Free from any obvious or significant wear. Perhaps it was only admired. Maybe just whispered to.
No scratches, scuffs, or signs of existential crisis.
GOOD
This disc has lived a good life so far. It has been loved and cared for. Passed from hand to hand with the normal wear you might see on a well-loved disc.
Possibly a light scratch or scuff that doesn't affect performance. The case may have some significant shelf wear.
ACCEPTABLE
The disc has been through multiple iterations of the universe. Still plays like a champ. TESTED. Expect visible scratches, scuffs, and perhaps a lingering resentment toward its previous owner.
The outer case may be stained, distressed, or non-existent (just like all of us).