Ya this question is like that of food.
Can a tray of McDonalds processed food (more 90s ish stuff) ever go bad?? probably not
Can a fresh banana go bad? yes (the darn things have gone bad in my car on the way home from the grocery store!!)
If truly organize materials and extracts are used (and certain types of unperfected VG) it will spoil and change colors.
Most of your typical counter juices will not go bad and I've even received pre- steep
juice that is 60 + days old.
It all depends on your organic materials used (or not used)
vape ON!!!!!!!!!!!!!!!