Richmond's service area sits in a severe cold climate band, and that matters for cables more than people expect. Cold doesn't snap a cable by itself, but it stiffens the galvanized wire and makes it less forgiving of the daily flex a cable goes through every time the door runs. Combine that with housing built mostly in the 1960s and 70s - a lot of it still on original hardware decades past its expected service life - and you get cables that have been flexing over the same worn drum groove or pulley for fifty-plus years.
Rust is the other piece. Winters here mean salt and moisture on vehicles pulling in and out, and cable near the bottom bracket picks up spray and road grit that original factory lubrication stopped protecting against a long time ago. Once a strand starts to rust, it's just a matter of cycles before it frays through.
This isn't unique to one neighborhood - it's a pattern across the whole service area given how much of the housing stock dates to that same build window. Newer doors with factory-coated cables hold up longer, but a lot of what's out there was installed before that coating became standard.