The oldest known written customer complaint is a 3,750-year-old clay tablet from ancient Ur, where a furious customer named Nanni accused the merchant Ea-nasir of delivering sub-standard copper — proof that bad reviews are almost as old as writing itself

Ancient clay tablets inscribed with cuneiform-style script.

In the British Museum's Mesopotamian collection sits a palm-sized rectangle of baked clay, catalogued as UET V 81. It is roughly the size of a modern smartphone, densely incised with cuneiform on b...