Why doesn't a pound of food that a cow eats turn into a pound of beef we can eat?

A pound of food consumed by a cow does not result in a pound of edible beef because of energy transfer inefficiencies, metabolic processes, and conversion inefficiencies. Only a certain percentage of the energy from the consumed food can be passed on to the next consumer in the food chain due to energy losses in metabolism. Cows use consumed food for vital functions such as respiration, digestion, and cellular repair, reducing the energy available for beef production. Additionally, cows have a complex digestive process for breaking down plant-based food, which further loses energy as heat. Overall, only about 10% of the energy available at one trophic level is transferred to the next level, resulting in a lower yield of beef compared to the weight of the consumed food.