Spring underrating for replacement
Most of this town went up around 1993, so the doors and openers are largely first- or second-generation replacements on original tracks. That's a specific window: springs rated for a lighter door than what's actually hanging, openers with drive systems that were standard in the early 90s and don't take modern safety sensors without an adapter, and torsion springs that are now past their cycle life if nobody's swapped them since the house was built.
