How does marginal product change in each stage of production?

In the stages of production, marginal product initially increases as more inputs are added, leading to greater efficiency and output due to better utilization of resources. However, after reaching a certain point, the marginal product begins to decline due to diminishing returns, where additional inputs contribute less to overall output. Eventually, in the final stage, the marginal product may become negative if too many inputs lead to overcrowding or inefficiencies. This progression reflects the balance between input and output efficiency throughout the production process.