Birmingham sits in a cold-moderate climate band, and Gardendale gets the same freeze-thaw swings - track rail contracts in a cold snap, the clearance between roller and rail tightens, and a roller that was already slightly worn catches instead of rolling through. On 1990s-era doors that's often the original steel track, now over thirty years in, with the same rollers it shipped with. Nylon rollers from that period wear a flat spot; steel rollers from that period wear a groove. Either way, the roller starts riding the edge of the track instead of the center, and eventually it walks off.
The other local factor is simpler: a lot of these doors were installed once, in the late '80s or early '90s building boom that shaped this part of the county, and never had the track realigned since. A door that's run for three decades on slightly loose track hardware is already closer to failure than a door half that age. That's not a Gardendale-specific defect - it's just the math of a housing stock that's aging into its original hardware's limits at roughly the same time.