Manufacturing is a one-way business. Raw materials go into a factory and finished products come out. Once those goods are sold, producers (initial guarantees apart) usually wash their hands of them. Certainly they do not worry, unless compelled to by law, about how the products are disposed of. Most are burnt or rot in landfill, which pollutes the planet. In only 50 years the world’s consumption of raw materials has nearly quadrupled, to more than 100bn tonnes, according to the latest Circularity Gap Report from Circle Economy, a research and consulting group. Less than 9% of this is reused, resulting in a big waste of materials.