In our modern and developing world, we need all types of materials, including various metals and plastics, to build appliances and equipment - our motor cars, cell phones, computers, home appliances and so on. The raw materials we need to build them, are largely extracted from the earth in mining or oil pumping operations. These items don't last forever and eventually need to be replaced if they can't be repaired. Now we know that we have only one earth available, and the mineral resources are not unlimited. In fact, they are getting more and more costly to extract as we need deeper and deeper deposits. It therefore makes great sense not to waste the metals and other materials that have already been mined, and which are in our scrapped appliances.
Furthermore, the mining and processing of metal ores and petroleum has a great impact on our environment, including the release of carbon dioxide (CO2) into the atmosphere, which is said to be having an effect on the weather. Large changes in weather patterns will result in dramatic impacts on our daily lives. Extracting metals from recycled goods requires a lot less energy and produces much less CO2 than if the same metals are produced from mineral ores, so it makes great sense to recycle as much as possible.
One day, ideally, we would like to be able to recycle almost all materials from scrapped items, so that the mining of new ores can be reduced to a minimum.