Here's why:
* Erosion: Over long periods, wind, water, and ice can wear down sharp peaks and jagged edges of mountains, creating gentler slopes and rounded summits. This process is called erosion.
* Weathering: The breaking down of rocks into smaller pieces (like freezing water expanding in cracks) also contributes to the smoothing of mountain features.
While other factors like tectonic activity (the movement of Earth's plates) can influence the formation of mountains, erosion is the primary force responsible for their gradual rounding and softening.
