Here's why:

* Oceanic Hotspots: These are the most common type of hotspots, and they are responsible for creating volcanic island chains like Hawaii. Oceanic hotspots occur when plumes of hot, buoyant mantle material rise from deep within the Earth and pierce the oceanic crust. This leads to volcanic eruptions that create underwater mountains and eventually emerge as islands.

* Continental Hotspots: Hotspots can also occur under continental crust. When a mantle plume reaches the surface under a continent, it can create large volcanic provinces known as Large Igneous Provinces (LIPs). Examples include the Deccan Traps in India and the Siberian Traps in Russia. These LIPs can be massive, covering thousands of square kilometers.

In summary:

* Hotspots are caused by plumes of hot mantle material rising from deep within the Earth.

* These plumes can pierce both oceanic and continental crust, leading to volcanic activity in both environments.

While oceanic hotspots are more common, continental hotspots also play a significant role in shaping the Earth's surface.