It is well known that motor Horse Power is
hp = TxRPM/5250
where T stands for torque and RPM is the motor RPM
So this means that for a given hp, lesser is the RPM more will be the torque. i.e which means that 6 pole motor shall have more torque compared to a 4 pole motor of the same Horse Power.
So then why do we use 4 pole motors instead of 6 pole motors?