Obedience is rendered for many reasons: duty, fear, coercion, greed or reciprocity, among other reasons.
The strongest compulsion is that of love. It is the most powerful and it lasts forever. Its dictates are transcendent and its mandates never dim nor expire.
No beauty was ever like that of the Messenger of Allahﷺ, nor was any love like hisﷺ.
Therefore it is befitting of any heart that has any life left in it, that it should love no other from the creation like it loves himﷺ.