West Linn sits in the same cold-moderate climate band as the rest of the service area, and that band drives a specific kind of wear. Grease on a chain or screw drive thickens in cold mornings and loosens again as the garage warms through the day, so a unit that runs fine at 2pm can grind and stall at 7am. Over a few winters, that daily tightening and relaxing works screws loose and strains the drive gear.
The build-year gap matters too. At a median of 1988, a lot of West Linn's original openers predate the point where photo-eye reversal sensors were standard factory equipment, meaning some of what's on the ceiling now is a retrofit added later, wired into an older board it was never designed for. Those retrofits are a common source of intermittent reversal problems - the sensor itself is fine, but the wiring run back to an old board isn't matched to it.