It is true that Marines, as well as other military personnel, are often seen wearing their watches backward. There are two benefits to wearing a watch this way. The first one is connected to the light that could be reflected from the watch’s face. The flash of light could give away your location to the enemy. By wearing the face inside your wrist, the sun is less likely to catch and reflect it. Another benefit to be gained is that the watch face is more protected from shattering when it is bumped against something hard. When sitting in the back of a striker vehicle or tank, the ride can get pretty bumpy. And if your watch face bangs hard against anything weighing more than a ton, the glass is very likely to break.