The cold moderate climate band covering South Hill and the rest of the service area doesn't bring the extreme cold that cracks concrete slabs, but it does bring enough freeze-thaw cycling to work on steel and rubber over a couple of decades. Weatherstripping on doors installed in the '90s and early 2000s is commonly past its useful life by now - it's not a dramatic failure, just a slow one, and it shows up as a draft along the bottom seal or daylight visible at the corners.
Moisture cycling is the other driver. Torsion springs holding tension for 20+ years in a garage that isn't heated or fully sealed lose consistency in how they wind and unwind, which is part of why spring failure on original hardware clusters heavily in houses from this build era rather than being random. None of that is unique to any one street - it's a function of when the house went up and how the climate here treats steel and foam over time, which is also why a straight repair-versus-replace call should factor in the door's age, not just its symptom.