The Appalachian Mountains are not actually smooth and rounded. They are jagged and rugged, with peaks and valleys. This is due to a combination of factors:

* Erosion: The Appalachian Mountains have been exposed to weathering and erosion for millions of years. This has worn down the peaks and created the characteristic rounded shapes.

* Uplift and folding: The Appalachians formed from the collision of tectonic plates, which caused the land to buckle and fold. This created the high peaks and deep valleys.

* Glaciation: Some areas of the Appalachians were covered by glaciers in the past. This glacial activity smoothed and rounded some of the peaks and valleys.

While the mountains are not perfectly smooth, they are much more rounded than younger mountain ranges like the Rockies. This is because the Appalachians are much older and have had more time to be eroded.

So, while the Appalachians may appear less dramatic than some other mountain ranges, they are still a testament to the powerful forces of nature that shaped them over millions of years.