Learning to keep your goggles on (and over your eyes) without removing them when you are swimming is a very good habit to develop. A swimming workout often includes a warm-up, a main set and a cool down. After each set, swimmers often put their goggles on their forehead and rest before the next set; however, the goggles then fog up, which is very annoying. Warm air and water cause the lenses to fog up. Yep. Also, when your goggles are adjusted “just right” on your face and eyes (yes, this can really happen), lifting them up and down off your face breaks the seal you have established. It is highly unlikely that you will be able to get that good seal again during your swimming set.