could be genetics - suprisingly hard to find plants that tick all the boxes, including flavor/aroma. Ccould have over-dried. could be higher temps at various points in process.
unlike tabacco, there's no chemical change occurring when "curing" marijuana so it's more about limiting the evaporation of volatile terpenes as best possible The terps with a high BP gas off at a much slower rate, but even those are affected in the long run by improper drying/curing. maybe, also about breakdown of certain other molecules not related to terps or THC. biodegrading is a "downhill" process and shouldn't take much effort to allow it to happen.. that portion of the equation just needs time, if it is relevant or not.
there's a lot of science-y sounding conclusions with fancy words and lots of confidence, but very little competent research has been done on this, so it's a wild guess by the peanut gallery just like when 'they' said flushing for harvest reduced mineral content of the flower -- sounds good, sounds rational, sounds science-y but absolutely not true when put to the test.
another example of this -- that green light is safe during a photoperiods dark cycle in flower phase... big fat nope to that nonsense, yet you'll find plenty that beleive it.
there's lots of mythology sorrounding this plant.. best guesses of the masses that have yet to be tested properly. it's nearly impossible to discern which hypothesis are good or bad without properly applying the scientific method. It's why our advances in the last 150 years are a million times more sophisticated than a 100,000 years of holistic medicine (shamans, witch doctors, etc...). For hundre thousand years that stuff failed 99% of the time, lol. modern medicine and science is not perfect but at least it weeds out the retardation, eventually.