Why is understanding the hydrologic cycle so important to understanding how landscapes form?

The hydrological cycle is one of the few cycles on the planet that have very big influence on pretty much everything on the planet. This cycle is also very important in the formation of the landscapes on Earth. The reason for this is that the water, be it in liquid, gassy, or frozen condition, is heavily influencing the surface of the planet. The large bodies of water manage to erode the rocks that they come in contact with. The rivers, especially the larger ones, are living fertile deposits in their valleys, setting up the terrain for dense vegetation. They also transport material from one place to another. The rain, and the runoff from it, mange to weather, erode, and create shapes in the landscape. The high amount of water vapor in the air contributes to quick decomposition of the biomass, resulting in fertile soil etc. Those are some examples, and there are many more, which just shows us that understanding the hydrological cycles is crucial for understanding the formation of the landscapes on our planet.