The safety threshold that settles it outright
Under the Consumer Product Safety Improvement Act of 1990 and UL 325, residential garage door openers manufactured for sale in the United States from 1 January 1993 must have external entrapment protection — the photo eyes near the floor. If your opener has none, it predates that requirement and it should be replaced, full stop. No repair economics apply to a door that cannot detect a child underneath it.
Repair the door, replace the opener — they age differently
A steel sectional door is a twenty-to-thirty-year product whose consumables are springs, cables, rollers and seals. An opener is a ten-to-fifteen-year electromechanical product. Treating them as one decision is the commonest mistake: a perfectly good door frequently outlives two openers, and a tired opener does not condemn the door.
The repair-versus-replace arithmetic
Repair when the door is structurally sound, the sections are straight, and the failure is a consumable. Replace when multiple sections are damaged, when the model is discontinued and panels cannot be matched, when the door has been off its track more than once, or when the accumulated repair estimate approaches half the price of a new door. Springs are the classic false economy in the other direction — they are consumables, and replacing them on a sound door is almost always the right call.
Where a new opener earns its price in California
Any opener installed in California must now include a battery backup, which is genuinely useful in a PSPS-prone state. Modern DC belt-drive units are quieter, connected units send a notification when the door has been left open, and warranty coverage restarts. On a fifteen-year-old unit, a board or gear repair often lands within a couple of hundred dollars of all of that.
The California factors that pull the decision earlier
Coastal corrosion shortens cable and spring life and eventually reaches the hardware and the track. Desert heat shortens opener life. A wildfire-zone address makes the perimeter gap and material requirements a reason to replace rather than patch. A soft-story retrofit changes the opening and can force a new door regardless of the old one's condition.
When you replace, replace properly
New springs specified to the new door's weight, new rollers, new cables, new bottom bracket, and a properly balanced door before the opener is even connected. Reusing tired hardware behind a new door is how a new door acquires an old door's problems in its first year.