I knew a few people when I was young (20s) that "pot does nothing" to them. Then one day they took a toke from a joint going round and were totally munged. I'

I knew a few people when I was young (20s) that "pot does nothing" to them. Then one day they took a toke from a joint going round and were totally munged. I've seen it a few times, and I have no idea why it's like that for some people.