I am coming around to the Hojo answer for FFVII. Mostly because I think intent matters, as does caring about the consequences of one's actions. I'd bet that neither Hojo or Yu Yevon intended for things to get as out of control as they did, but neither did they worry too much about the possible side effects of reckless experimentation/conjuring a powerful weapon.

I'm also starting to wonder how differently these results might have come out if I'd included groups of people along with individuals -- ShinRa, Yevon, the Occuria.