What 98% of directors and screenwriters don’t understand is that professional assassins like to be covert. Certainly the corporate kind. They don’t like to make noise or draw attention from onlookers or do anything that might result in any kind of whiff or trail. The best way to ice someone, obviously, is to make it look like they didn’t get iced. Give them a heart attack, stage an accident of some kind — anything but an outright murder.