Wax additives are designed to change the character of your wax. If you need to increase the durability of a wax, say in icy conditions or on man-made snow, you can add a hardener. If you need to increase the hydrophobic qualities of a wax, for wet now conditions or high humidity, you can add fluorocarbon. Graphite or molybdenum can be added to a wax to decrease static and increase dirt repellency. Additives allow you to fine-tune a wax to match the conditions you encounter.