Since I began my flying career I've always been told of certain switches in airplanes that are killer switches. What this means is every airplane have a switch, or two that you need to pay close attention to detail to. You need to guard against it so to not to unintentional activate it. Most people are amaze of all the lights, buttons, and switches in modern jet airliner. People tend to think that airplanes will drop out of the sky if a pilot made an error with the wrong switch. This is not really the case. Unless its the rare exception of the killer switches. Usually just one, two switches are very important in most airplanes. In most cases aircraft engineers design those switches with safety in mind. In most cases, they are color guarded in red, or yellow to grab a pilots attention. Some are safetied wire shut so that in order to activate it you actually have to make an effort to break the wire to activate that switch. The purpose of this is to insure the flight crew read the checklist before touching any switch. So as you could see its very difficult to activate ,or turn on a killer switch unless your incredibly reckless person.