This isn't related to suicidal thoughts or anything like that, there has to be some sort of a psychological reason in humans. When I was about 4 years old I looked over railings on a bridge, looking into the river below and wanted to jump. Was it just because I wasn't entirely aware of what drowning is? I thought that if I jumped in I'd wake up from a dream. Or is there really the "forbidden fruit" attraction to wanting to jump off in such cases?