Subscribe to our newsletter. We've all been subject to it at one point or another. Edward A. Murphy, Jr. was a real man. He worked as an engineer on rocket-sled experiments for the US Air Force in 1949. This was quoted by the slightly-beaten test subject days later in the news.
Nothing is as easy as it looks.
Everything takes longer than you think. Anything that can go wrong will go wrong. If there is a possibility of several things going wrong, the one that will cause the most damage will be the one to go wrong. If anything simply cannot go wrong, it will anyway. If you perceive that there are four possible ways in which a procedure can go wrong, and circumvent these, then a fifth way, unprepared for, will promptly develop.