In a rinse-off shower gel, ingredients like glycerin and hyaluronic acid work temporarily on the skin's surface during the brief contact time of your shower. They act as humectants, attracting and binding water molecules to the skin. While they are rinsed away and do not provide deep, lasting hydration like a leave-on cream, they can help modify the immediate post-wash sensation. The goal is to reduce the tight, stripped feeling that some cleansers leave behind, making the skin feel softer and smoother after drying off. For a more noticeable hydrating effect, pat your skin gently with a towel instead of rubbing it dry after showering, as this leaves a thin layer of moisture on the skin that the humectants from the gel can briefly help retain.