Well, you apply water on your lips. Applying water alone or in combination with aquaphor can certainly help. I used to think I would always need to apply something on my lips. After not needing to apply anything, I see that it's not normal to need to apply something although lips are the driest area of the face. I'm just saying don't give up looking for the cause, but do what you're doing to handle it since it's working well for you.