If you perceive that there are four possible ways in which a procedure can go wrong, and circumvent these, then a fifth way will promptly develop. Left to themselves, things tend to go from bad to worse. Whenever you set out to do something, something else must be done first. Every solution breeds new problems. It is impossible to make anything foolproof because fools are so ingenious.
Nature always sides with the hidden flaw.
Mother Nature is a bitch. O'Toole's Commentary on Murphy's Law Murphy was an optimist. Everything goes wrong all at once. The Unapplicable Law Washing your car to make it rain doesn't work. It will not work the first time.