Imagine that you were going to kill someone. What do you think would be the most difficult part? Three, two, one... time's up! The correct answer: killing someone. Now, now, calm down — I swear I'm not making fun of you, or playing linguistic tricks here. I'm completely serious. People, in other words, humans, have not been designed to die that easily — at the least, people almost never grunt or moan and immediately fall over dead. Strangulation, blunt force trauma, stabbing — none of these kill people easily. Humans are surprisingly sturdy creatures. Additionally, people have a tendency to resist being killed. Nobody wants to be killed, and there's a good chance they'll try to kill you back.