This isn't a generic wear-and-tear story - it's tied to what's actually sitting in garages across this area. With a median build year of 1978 and most stock dating from the 1960s through the 70s across the eleven named neighborhoods here, a lot of doors are still running on original or first-generation replacement rollers, often the narrower track style that was standard on that era's builds. That hardware wasn't designed with this region's winters in mind.
Spokane Valley's climate band is rated severe cold, and an unheated or uninsulated garage puts those rollers through a hard freeze-thaw cycle every winter for decades. Plastic and nylon rollers get brittle under that kind of repeated cold stress in a way they wouldn't in a milder climate, which is exactly why we see this fault cluster so heavily in the older sections of the service area - from Veradale two miles out to Liberty Lake six miles east, and out through Otis Orchards and Mead. The same build era, the same hardware, the same climate exposure, call after call.