My stove died at 9,000 feet in Rocky Mountain National Park
I was three miles up the Flattop Mountain trail last October when my old MSR WhisperLite wouldn't pressurize. Turned out a tiny piece of grit was stuck in the jet, and I had to dig it out with a pine needle.
Hiked up to a lake in the Winds last summer and my buddy's stove wouldn't light either, turned out he forgot to open the fuel valve at all. We sat there for twenty minutes trying to figure it out before I checked and felt like an idiot for him.