Reasons for applying glycerine on lips in winter:
Glycerin is applied to the lips in winter. In winter, the air has less water vapour. During this time the wind absorbs water vapour from the exposed soft parts of the body such as lips. As a result, the lips are cracked. Applying glycerin stops chapped lips. Glycerin absorbs water vapour from the air and prevents water vapour from evaporating from the lips.