Livermore's housing stock sits mostly in the 1961-2010 range, with the bulk of it built in the 1980s and 90s - a period when torsion spring gauges and standard chain-drive openers were installed to a builder-grade spec, not an upgraded one. Thirty-plus years on, those original springs are past their rated cycle count on nearly every house that hasn't already had one replaced.
The climate here is mild temperate, so we're not dealing with the freeze-thaw cracking or the swelling wood panels you'd get somewhere with hard winters. That's the good news. The failure mode here is almost entirely cycle fatigue and metal age, not moisture or ice - springs and cables just wear out from being opened and closed thousands of times over three decades, and rollers dry out and crack rather than rust.
Because the surrounding area, from Sunol out to Byron and Brentwood, shares that same 1980s-90s build era, we see the identical failure pattern on a lot of these builder-grade doors: same spring size, same opener chassis, same age of decline.