When it is certain that one must mingle with the dust after death, what purpose does a marker upon the grave serve?

In this touching couplet, the poet reflects on the futility of human pride and our longing to be remembered after we are gone. If our ultimate reality is to simply dissolve back into the earth as dust, what real purpose does a gravestone or marker serve? It carries a quiet peace, inviting us to embrace humility and accept the fleeting, nameless nature of our existence.