Pleasant Grove's median year built sits at 1986, about six years newer than the median across the whole Birmingham service area, which runs 1957 to 2007 with a median of 1980. That six-year gap matters more than it sounds. Doors going up in the mid-1980s almost never came with the single-spring, extension-cable setups you still find on the older 1960s stock closer to the city. By '86, builders in subdivisions like this one were putting in steel sectional doors on torsion springs as a matter of course, usually a single torsion spring sized for a 7-foot door rather than the pair you'd expect on something wider or older.
That torsion spring is galvanized, rated for a set number of open-close cycles, and it's now been doing that job for close to forty years. When it lets go, it lets go all at once, and the door drops. The opener on these houses is often the second or third unit installed since the home was built, which means the garage door itself usually outlasts two or three openers before the spring finally gives out. That's the fault we see first here, not the frame or weatherstrip issues you'd expect on an older build.