Housing across this part of the county went up mostly between 1970 and 2003, with the median build year sitting around 1983. That means a huge share of the doors on the streets around Cardiff, Leucadia, and the neighborhoods stretching toward Carmel Valley and Del Mar Heights are running original or first-replacement hardware that's now 20 to 50 years old. Springs, rollers, and cable are wear items with a life measured in cycles, not years, but a door installed in 1983 has put in a lot of cycles by now.
The climate here is mild temperate, which cuts both ways. There's no hard freeze-thaw cycle to crack seals or seize hardware overnight, so a lot of owners assume the door will just keep going with no attention. It won't. Slow, steady wear - dried-out lubricant, a roller that's worn oval instead of round, a spring losing tension a little at a time - doesn't announce itself the way a winter failure does elsewhere. It just gets a little worse every month until the day it doesn't open at all.
Across the roughly 10,803 owner-occupied houses in this service area, the pattern repeats: doors from the 1980s and 90s stock are aging out of their original hardware right now, on a mild schedule that hides the problem until it isn't hidden anymore.