Why are cameras / camcorders waterproof to certain depth?

This just came up in my mind, How come cameras / camcorders are waterproof only to a certain depth. Like the kodak playsport, it says it’s waterproof only down to 10 feet or something. What happens if you go lower?

As you go deeper, the water pressure increases. The seals designed to keep the water out of the inside of the camera/camcorder are not designed to handle the pressure.

When you get to about 10 feet, your ears can feel the effects of that pressure.

The underwater camera or camcorder housings that are made for 100+ feet depth will typically cost more than the camera they are protecting… The deeper the housing is rated, the more challenging it is to engineer and make and the more expensive it is.

DICAPac Waterproof Cases for Digital Cameras & Cell Phones