Sod's law
who or what is sods law
SOD'S LAW - "inf. If anything can possibly go wrong with a test or experiment, it will. Originally applied to the natural sciences, the use of this law has been extended to cover day to day living and reads simply, 'If anything can possibly go wrong, it will,' to which has been added, 'and it will happen at the worst possible moment.'" The U.S. equivalent is "Murphy's Law." From British English: A to Zed by Norman W. Schur (Harper Perennial, New York, 1987).