Housing in this service area runs from 1948 through 2014, with the median landing around 1977, and the bulk of it clusters in 1960s and 70s construction across the 91 named communities we cover. That era of door hardware was built for a milder duty cycle than what it's gotten. Pair that with a cold-severe climate band, and you've got steel torsion springs that contract hard every winter night and expand every time the sun hits the door face, cycling through a wider temperature swing each year than the spring's rated fatigue curve assumes. Forty-plus years of that cycling is exactly why so many of these doors start showing cable fray and spring sag around the same age, regardless of how well the door was maintained. It isn't bad luck - it's the math of an old steel part living in a climate that stresses it twice a day. Newer builds in the area, going up as late as 2014, mostly dodge this because they're running springs and openers rated for current load and temperature standards. The older stock is where the calls come from.