Not just the ignorant — even the wise are hounded by this enemy. Krishna calls desire the 'nitya vairi,' the perpetual adversary of the one who seeks knowledge. It does not rest. It does not retire. It returns again and again in different forms.
And it is 'dushpurena analena' — insatiable, like a fire that only grows hungrier the more you feed it. Pour ghee into a fire and it flares higher. Give desire what it asks for and it immediately asks for more. This is why the enemy cannot be appeased. It must be understood and overcome.