A garage door spring that's already groaning, sagging, or visibly stretched won't get better on its own, and waiting through another cold season is one of the more expensive ways to find that out. Cold snaps make steel more brittle, so a spring that's been creaking along since summer is far more likely to snap during a January morning than a mild October afternoon. A sudden break doesn't just mean an inconvenient trip to the hardware store — it can mean a door that's stuck shut over a car you need for work, or stuck open and exposed to heavy rain and wind during a coastal storm. Replacing a spring before it fails is almost always cheaper and less disruptive than replacing it after it fails, especially if the break damages the opener, cables, or track on the way down.