It is VERY difficult to get right. Single stream recycling practices (ie putting all your recycleables in the same bin) was a critical blow to plastics recycling. Not only are the plastics intermingled with non-plastics, but the various polymers are intermingled with each other. And on top of that they are covered in contaminants such as food, labels, metal, glue, etc. People have no idea how little of their plastic actually gets recycled. It is a tiny fraction. The problems are (1) efficiently identifying polymer types, (2) sorting the plastics based on polymer type, (3) decontaminating, and (4) producing a ground or pelletized product that meets the specifications of downstream manufacturers. All of this aginst the backdrop of incompetent regulation that makes everything more combersome and expensive. The vast majority of plastic ends up in land fills or are sent to China, Viet Nam, etc where they are sorted manually for cheap. There is a multi billion dollar company waiting for anyone who figures out how to identify, sort, clean, and pelletize to spec a mixed 1-7 bale in a totally automated fashion.