One might think there is some reason for such statements, since the pressure that the water exerts deep down in the ocean is indeed tremendous. At ten meters down, the water exerts a pressure of 1 kg to every sq. cm of the submerged body. At 20 meters down, this is already 2 kg, at 100 meters, it is 10 kg, and at 1,000 meters, it is a whopping 100 kg.