How hard does it take to extract Italian concentration to press the powder? What will be caused by the different intensity of powder pressing on extraction?

The powder press (or powder hammer) is one of the most commonly used tools in espresso. The main purpose is to flatten and tamp the coffee powder in the handle to form a flat horizontal plane, to better let the hot water be extracted through the coffee powder, and to make the coffee powder withstand the great pressure caused by the coffee machine extraction. without being washed away and impressing the quality of the extraction. The force of pressing powder needs root.