When composting your return on on lets say a full compost bin is probably around 1/3of the bin. The reason you compost the CM is that fresh chicken poo is very high in nitrogen. If you put it in your garden it will burn the plants. What composting does is build up heat and breaks down material.The heat it generates usually kills weed seeds and harmfull pathogens.The more you turn your compost, the more oxygen you add to the pile. the faster those materials break down. High nitrogen materials IE, Chicken manure/grass clippings create heat, the brown material( hay, strw leaves, wood shavings) are the carbon and when they go through the heat cycle you have finished compost. It balances out into a very good fertilizer for you soil. I have three compost bins going now and it amazes me the amount material these thing eat.I packed them to the top in the spring and add things all summer long and when the composting is finished I have less then 1/3 of a barrel. Land fill wise, I would say 5 large garbage bags of material will compost down to less then one bag of compost. I just started with chickens and cant wait to get the manure in the compost bins.I used to get horse manure.Its Black gold in its finest natural form.