Most of the houses across this service area went up in the 1960s and 70s, with the broader range running 1943 to 2012. Doors on homes from that first wave have had sixty-plus years of sun, and steel panels from that era don't flex the way newer composite or insulated sections do - they dent and stay dented instead of springing back.
The climate here is mild temperate, which is kinder to doors than a region with hard freezes, but it's not nothing. Steady sun exposure on south- and west-facing garage doors fades paint and dries out the seals between panels, so a panel that's already a little brittle from age cracks instead of flexing when something hits it. We don't see the ice-related panel splits that cold-climate companies deal with, but we do see UV-brittle steel and rust at the bottom panel edge, where sprinkler overspray or a slow slope toward the door keeps that one section wet longer than the rest.
Houses built later in the range, into the 1990s and 2000s, tend to have composite or insulated steel panels that take an impact better, but even those crack at the corners if the door's been out of alignment for a while before anyone calls.