What degrades THC?

Answer 1

just like any plant, fruit herb or nut, fruitful or not, over a particular time period (even if vacuum sealed etc) will lose its potency, whether that be related to vitamin content, mineral or other.

Answer 2

THC can degrade over time due to exposure to oxygen, light, and heat. Oxidation breaks down THC molecules, while UV light can also degrade them. High temperatures can speed up the degradation process as well.