Here's why:
* Plate collisions create fold mountains (like the Himalayas) or block mountains (like the Sierra Nevada) due to the immense pressure and uplift caused by the plates pushing against each other.
* Volcanic mountains are formed by the accumulation of lava and ash erupted from a volcano. This eruption is caused by magma rising from the Earth's mantle and finding its way to the surface.
While volcanic activity can be triggered by plate movements (like at subduction zones), volcanic mountains themselves are not directly formed by the collision of tectonic plates.
