Most of the houses across this service area went up between 1953 and 2014, with the bulk of the stock dating to the 1980s and 90s - doors old enough that their factory rollers have outlived their bearings. That's the housing wave you see from Grand Prairie six miles out to Kennedale seven miles east: garages built in the same decade, fitted with the same builder-grade steel rollers, now failing at roughly the same age.
The area's moderate heat band doesn't cause the kind of hairline concrete cracking you get in freeze zones, but it does put steel through a slow expand-and-contract cycle every season. Roller stems that were never sealed pick up surface rust in that cycle, and rust plus a stamped-steel bearing is a bad combination. You get a groove worn into one side of the roller, and once that groove is there, the wheel doesn't sit flat in the track anymore.
With 97,142 owner-occupied houses spread across 189,893 households in this corner of North Texas, a lot of those original doors are still running on the rollers they shipped with. It's not a defect. It's just a part with a service life, and that life is up.