Daily moisturizers are not needed if you regularly deep condition your hair once a week. Moisture should stay in your hair strands long enough till your next deep condition. With regular deep conditioning and the intake of the recommended amount of water, your hair should stay well moisturized. If your hair is extra dry and continues to be dry regardless of your deep conditioning and water intake, you may need to check the pH balance of your hair, but in the meantime the use of a light daily moisturizer can help you.