وعن أبى مريم الأزدى رضي الله عنه
أنه قال لمعاوية رضي الله عنه سمعت رسول الله صلى الله عليه وسلم يقول: «من ولاه الله شيئاً من أمور المسلمين، فاحتجب دون حاجتهم وخلتهم وفقرهم، احتجب الله دون حاجته وخلته وفقره يوم القيامة» فجعل معاوية رجلا على حوائج الناس
I said to Muawiyah (ibn Abu Sufyan) (radiyallahu anhum): I heard Messenger of Allah (sallallahu alayhi wa sallam) saying, “If Allah invests to someone the affairs of the Muslims and he (i.e., the ruler) ignores their rights, denies their access to him and neglects their needs, Allah will not answer his prayer or realize his hopes and will act towards him with indifference on the Day of Resurrection.”
So Muawiyah appointed a person to keep a vigil on the necessities of the people and to fulfill them.