The Messenger of Allah (may Allah's peace and blessings be upon him) appointed a man in charge of an army unit who led them in prayer; he always concluded his recitation with Sūrat al-Ikhlās

The Prophet (may Allah's peace and blessings be upon him) appointed a man in charge of an army unit to be in charge and judge between them so that everything take place in an orderly fashion and without chaos. He chose the most religious, knowledgeable, and expert one of them. For this reason, rulers and scholars were to lead the prayers due to their knowledge and religion. He always concluded his recitation with Sūrat al-Ikhlās in the second Rak‘ah of every prayer because of his love of Allah and His names and attributes. It is natural whenever someone loves something that he increases its remembrance. When they returned to Madīnah, they reported this to the Prophet. So he said: "Ask him why he does this!" Is it a coincidence, or is there a special reason? The leader said: "I do this because this Sūrah contains the attributes of the Most Merciful and I love to repeat it because of this. So the Prophet (may Allah's peace and blessings be upon him) said: "Inform him, just as he repeats this Sūrah - because of what it contains of Allah's beautiful names and attributes and because he loves it - Allah loves him as well."