This is debatable. But, drinking liquids means your metabolism is getting its fluids so isn't dehydrated ; dehydration leads to dry skin, premature wrinkles etc Flavoured liquids might mean sugared liquids which usually means the body isn't getting its full fluids from the drinks. I suggest drinking a good litre of water or so and on top drink whatever you want! Then you can't go wrong!
Myth....I never drink water and dont have spots/lesions or any skin probs. Complexion has a lot to do with environment....a good brisk walk does lots to freshen face and skin.