Wondering about garage door torsion springs? The second link in particular is a great resource.
Garage door springs are normally manufactured to last for 10,000 cycles. However, it is possible to have a high cycle count conversion on a stock garage door spring to bring it up to 20,000 cycles. However, it’s important to consider the relative life of the other components, the bearings, the rollers, the track, the cable, the torsion tube, and so on. Also, if your garage does not have a steady foundation, the shifting garage foundation can cause you trouble with those other components going out of alignment and getting damaged at an earlier date. When that happens, excess stress is placed on the garage door torsion spring, effectively reducing its lifetime. Likewise, having an insulated garage to regulate the temperature inside can improve the life of the garage door spring too: great stress can be placed on the spring when used in the cold.
So, one thing to consider is that maybe only the best springs are suited to the best built garages.
Finally, one last point. Zinc galvanized springs or oil tempered springs? The zinc galvanized springs are resistant to rusting, but that doesn’t mean they necessarily last longer. Most importantly, although they look prettier, they can make a quite aggrevating noise when they are in use. Go with oil tempered springs or both (oil tempered zinc galvanized springs?) if possible.
20180727/DuckDuckGo high reliability garage door spring
20180727/DuckDuckGo high cycle garage door spring
20180727/http://www.martindoor.com/blog/26-2011/150-springs-that-last-a-lifetime
20180727/https://www.garagedoornation.com/blogs/home/15332253-oil-tempered-versus-zinc-galvanized-torsion-springs