Marginal values are valid for a specific range of variables. They change as soon as a modification is induced in either the independent variable or the dependent variable. The marginal effect is the instantaneous change brought by the slight variations in the variables. It is non-zero if independent and dependent variables have values within a specific limit. The optimizer is developed to calculate marginal values. Then a profit calculation concerning a particular model is done. Marginal values are crucial in the refinery because they help prevent quality giveaways. Refiners can avoid infeasible problems with the help of marginal values. This topic will discuss the concept of marginal values, cause and effect of marginal values, usage of marginal values to avoid infeasibility and giveaways, the breakeven point for the cost of components, etc.