I got gifted a few sessions of 'stop smoking' hypnosis, by my then-gf. I was dubious about it being pointless- I'd always heard that hypnosis is basically fake. But it was a gift, money already spent, so I didn't want to waste it.
I went through the full 4 sessions that I was given, and despite my doubts, I really did try to go with it. The first few sessions, I just straight-up told the guy "Sorry, but this just isn't working. I feel completely normal". But he kept insisting that "No, it really IS working, you ARE getting hypnotized. You're just not noticing it!! You've just got the wrong the wrong idea of what to expect hypnosis to be like, from movies!!"
But every session, about 10 or 15min into the hypnotist's script, he did this kind of test, to see if you've "under", where he says "Your arms feel incredibly light, like helium balloons" He builds it up for a while, then he says "You arms are SO very light, that they're floating up in the air!! You're not TRYING to lift them- It's totally involuntary. But no matter how much you resist, you just can't stop your arms from floating up, above your head..."
The first few sessions, I guess I was still hoping all this crap MIGHT work, so I sat there, waiting for my arms to magically float up... which they didn't. We both just sat there like idiots, while he repeated that bit of the script, to no effect.
But the last two sessions, I thought "Fuck it. Maybe if I just play along, THAT will somehow make the hypnosis work" Or, it would be less awkward than hearing him repeat the "your arms are floating away" line 57 times, at least. So when he got to the "floaty arms" bit", I just play-acted it, and lifted my arms up. The hypnotist was rapt, saying it was "a breakthrough". But, obviously, I still felt nothing, it was all just a waste of time.
So after the final session, I said to the guy "Look, to tell you the truth, nothing really changed from my first sessions. I just deliberately, consciously lifted up my arms when you told me to. It wasn't involuntary- It was just exactly like any other time I decide to lift my arms." But again, he insists that no, I WAS really hypnotized, and in a trance, and that lifting my arms WAS involuntary.
That was like ten years ago, and I'm smoking a cig as I type this- I haven't gone 24 hours without smoking, since I was 15 or 16 or something.