The region sits in a cold-moderate climate band, and on hardware that's been in the ground since 1961, that cycle of freeze and thaw works on metal that's already fatigued. A torsion or extension spring rated for a certain number of cycles doesn't care how old the house is, but older springs in Belvedere Park were often undersized even when new, by standards that have since tightened. Add in decades of temperature swings and the failure point moves up - a spring that might run another five years in a newer, better-matched setup gives out sooner here. It's less about any one dramatic event and more about an older spring doing a harder job than it was built for, year after year, in a climate that doesn't let metal rest.