Question on garage door springs breaking?

No. The temperatures in your garage are no where close to a temperature that would affect the metallurgy of the spring. What affects the spring is the strain, and the strain is designed that it breaks after 12 years. (number of stain cycles)

What part of the spring are you "lubricating"?

Maybe the springs are adjusted to tight, have the tension less. The tension should only be to assist if the opening and then hole the door . Not to wizz the door up at 100 mike an hour, that is dangerous, and it breaks the door parts.

If the spring was rubbing on the metal door flange is about the only reason why the spring failed. Or where it actually hooks into. Oil has no effect on the spring, just where it is making contact...or the spring is overstretched even in the relax mode(when door is closed)

Mine have worked for 40+ years.

The springs most often break from metal fatigue. Depending on the quality of the manufacturers product they can last 1 year or twenty years! Ambient temperature has no bearing on the springs lifetime.

should not have any effect. those springs should last decades -- change brands

Not necessarily. I had to replace my entire door and spring about 20 years ago because of a fire. About 3 years one side broke and had to be replaced, it was an insulated door. The metal on tone of the spring failed.

not likely, what makes you think lubricant can stop metal fatigue from happening ?

The average lifespan of those springs is 7 to 9 years, depending on how often you open and close the garage door. Spraying WD-40 along the spring coils about every three months can help.

I seriously doubt that any of those things make much of a difference. It is probably more dependant on the quality of the steel used to make them as well as how often the door is opened and closed.