Because our body temperature is equal to the body temperature at any point of our body, or in other words at every point of our body the temperature is same. But there are few points  in our body where there can be difference of 0.5--1 degree celsius. tempt. Which we can't even sense that. hence, equal temperature means equal kinetic energy and there will be know energy transportation so we won't be able to sense the temperature on our simple words the temperature of our fore head is same as our hands