Why does polio only target motor neurons?

Tropism: Certain infections cause problems in specific parts of the body because there are places for the virus to attach there- this is called "tropism" I have attached a link that explains this is further detail https://en.wikipedia.org/wiki/Tissue_tropism

CellsThatActivateMus: It destroys the nerve cells which activate muscles.Those are the nerve cells it destroys. It destroys the motor neurons within Spinal cord at the Anterior Horn Cells.In the Brain Stem and Motor Cortex in the Brain.It leads to the development of Paralytic Polio