If you store a professionally pressed optical disc in an environment with good temperature control and low humidity, it may last 50 - 100 years.

Reduce that to like 1 to maybe 5 years if it was being played in an original X-Box with a Thompson disc drive. (If ya know, ya know.)

I'm still salty about being so careful with all my discs and watching Crimson Skies and Halo: Combat Evolved load backwards before showing "Disc Read Error."