Most of the housing across this service area went up between 1962 and 2005, with the typical home dating to 1983. That's a specific window: steel roll-up doors on side-mounted tracks, hung with the hardware that came standard for that era. Thirty-five years later, the brackets holding those tracks to the framing have been through thirty-plus winters of expansion and contraction, and a lot of them were never re-torqued after the house settled.
The climate band here is cold and moderate, not brutal, but it's consistent. Repeated freeze-thaw cycling doesn't crack concrete overnight, it works mounting screws loose a sixteenth of an inch at a time. A track that's fine in July can be a quarter-inch out of plumb by February, and that's enough for a roller to walk off the lip on a hard stop.
Across the 35 named communities this shop covers, the housing stock skews the same way: 1980s and 90s construction dominating the mix. That means we see the same failure pattern from one town to the next - not because the doors are bad, but because they're all the same age, hung the same way, and aging out at the same time. It's a maintenance gap more than a manufacturing defect.