Despite pilots’ most intense desires, airplane components wear out. Fortunately for their wallets, the major stuff on general aviation airplanes that are hangared and flown a few hundred hours a year—the airframe parts and pieces—should last the better part of a century. Along those lines, the things used by pilots to see through portions of the airframe, the windows, generally have a useful life measured in decades.
I’ll note here that the windows on your airplane probably aren’t glass, they’re acrylic, though I’ll sometimes use “glass” as a shorthand term. The enemies of acrylic windows are sunlight, dust, chemicals and scratches.