What leads to the unevenness or sinking of driveways?

The unevenness or sinking of driveways can result from a variety of reasons, such as erosion of the soil underneath, insufficient compaction of soil prior to laying down the driveway, the gradual settling of the ground, and problems with water runoff or poor drainage. These issues can create empty spaces beneath the surface, resulting in parts of the driveway sinking or developing an uneven appearance.