I have heard plenty of stories about unscrupulous contractors who cut corners but this one takes the cake.
During the cold war years , many people lived in fear of a nuclear holocaust. One business tycoon in Italy was terrified of what would happen to his family in case of a nuclear war and he decided to commission an atomic bomb proof bunker to be built in his garden. The contractor warned him that it would be very expensive because it would need high strength concrete and special alloy steel. But the tycoon was undeterred; he wanted to protect his family at all costs. The bunker was duly completed but then the unthinkable happened. One of the builder’s trucks bumped into the corner of the bunker and it came tumbling down like a house of cards. Investigators said that too much sand and not enough cement had been added to the mix. So much for the bunker for the bunker that was supposed to withstand an atomic bomb!