At the most basic level, all businesses are very similar. All businesses take in some kind of raw material, whether it is iron ore, ingredients or information, processes it in some way, and outputs finished products. These business processes are always subject to restrictions that limit the maximum production capacity. When one of these restrictions severely limits production, it is often referred to as a bottleneck. One of the primary challenges of business process management is to find and eliminate bottlenecks in production.