Washing your face with water is a first step towards a skin care routine. However, since tap water often contains limestone, it can lead to deposits of lime residue on the skin, which, in the long term, can lead to impurities. Also, some germs, viruses and bacteria that accumulate on our skin throughout the day are only fat-soluble, which means that they cannot be completely removed with water. A surfactant, found in cleansers, is necessary to prevent them from spreading on the skin.