Keystone's housing is older than most of what this company covers - median build year around 1978, against a service-area median closer to 1989. Older stock means older track hardware, and this part of South Dakota runs a severe cold climate band, which matters more than people think. Steel track contracts in deep cold, and a bracket that's been slowly working loose over 45 years of freeze-thaw cycles doesn't need much to finally let a roller jump. With only about 138 households in Keystone itself, a lot of these doors have had one owner's worth of maintenance, not a rotating set of fixes - so when a track finally goes, it's usually going because of age, not a one-time accident. That's a different failure pattern than you'd see on a door that's fifteen years newer, and it's why the first question on a Keystone call is always how old the house is, not just how old the opener is.