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. If everything seems to be going well, you have obviously overlooked something. Nature always sides with the hidden flaw. It is impossible to make anything foolproof because fools are so ingenious. Whenever you set out to do something, something else must be done first.
Every solution breeds new problems.
Two wrongs are only the beginning. If at first you don't succeed, destroy all evidence that you tried. Success always occurs in private, and failure in full view. Should you find something on your dinner plate that doesn't appeal to you, don't complain. There are people who don't have anything on their plate.