What are the significance of Cost volume profit analysis?

What are the significance of Cost volume profit analysis?
CVP commonly known as cost-volume-profit analysis is used to determine how changes in costs and volume affect a company's operating income and net income. There are assumptions made, including: sales price per unit is constant, variable costs per unit are constant, total fixed costs are constant, everything produced is sold, costs are only affected because activity changes, and if a company sells more than one product, they are sold.