If you vape for a while and come back, you start tasting weird tastes in the cigarette you didn't taste before, or got immune to. It really is quite sickening, but sometimes it's what somebody needs to make sure they made the right choice.
I had only vaped for 3 days and when I tried a cig it hit my gag reflex instantly. It is truly awful and I had smoked for over 20 years. Once you start looking for flavor in ecigs you taste the flavor of death in the analogs, and I don't know why anyone would ever go back.