Why do oceans lakes are rivers not dry up?

Well, some lakes and rivers do dry up. For example, much of the deep bore water in Australia last fell as rain thousands or millions of years ago.

The Great Artesian Basin underlies about one fourth of Australia, and is being mined faster than it is being replaced! Up to 2 million years old!

At Birdsville, the water temp is over 90oC, and is used as a source of geothermal energy.

The Caspian Sea has dried significantly, due to extraction of water for irrigation. A major ecological catastrophe.