The target's thought process: Oh look someone's coming at me with a knife. I'm thirsty. I think I'll ask them for a coffee! *dies*
The guard's thought process: Hey there's a man in a black suit! Shoot at him! *10 seconds later* Oh let's go back to out job. Oh look the boss is dead! Find the assassin! *10 seconds later* Let's go back to protecting the boss.