I never believed in hypnosis, what changed was my understanding of what people actually claimed hypnosis could do, and this change was the only constant thing about hypnosis. My father (an engineer) was down-to-earth enough to explain me math, physics, chemistry, ...

I do believe though in the somewhat debilitating conditions that exacerbate for a person who is already tired, like seeing repetitive long period highway lights, or road markings ... and of course innate primordial fears and reflexes...