In a busy plant, ensuring small changes don’t produce unforeseen toxic impurities is key
I often compare a working chemical plant to a particularly busy restaurant. The chemists plan the dishes and develop the recipes, and the operators are out in the plant, cooking up the product. The customers are hungrily waiting for their compounds to be shipped to them, asking the waiters (the salespeople) how their orders are coming, and whether or not their products have been tested in the quality control laboratory.