What is the meaning of [Spare the rod, spoil the child]

“Never count your children twice.” An old saying from the Anglo-Welsh border, where it was believed to be unlucky to do so. This saying arises from old superstition, which may have been contributed to in part by the terrain, which is rugged, hilly and sparsely populated; the region is also often subject to dense fog and disappearances under mysterious circumstance were not uncommon. Hence, the unlucky nature as on the second count, it was believed one child would most likely have disappeared; lost forever to the hills.