Water Resistant

Can I use a water resistant watch to go diving?
I bought two dive watches waterproof "good to 600 feet. The first leaked the first time in the water, the second lasted a year before the flood. These watches were expensive $ 80, too. In my second clock was no longer under warranty, I took the advice of a veteran diver "Go to Rite Aid and get yourself a watch under water by $ 20." He said, "I've been diving with mine during two years. "However, I am confused with the specifications: Water resistant to 100 feet or three rooms – a light shower or bath is fine, but NO diving or snorkel. By the way, I know that 100 feet is four environments. How can you say "water resistant to 100 feet" when it's only good for light rain or swim? Has anyone used one of these watches (SHARP) to go diving with?
u should have a water resistant watch. Ive been swimming w / One 4 a while, and any depth, fine.
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