The natural order for the human being is disturbance and disquiet. The state of the heart outside of dhikr is one of agitation. It is with the dhikr of Allah that the heart becomes tranquil.
Everything has a courtesy to it and you can define the courtesy as the rules that are concerned with the quality of what you are doing rather than the outcome of what you are trying to achieve. So it’s the rule whereby you give attention to the process rather than the outcome, what you are doing rather than the result.