In most cultures, there are unwritten laws, norms, or protocols. When the head of a national government arrives in the limousine, there will be guards who will open the door for the dignitary to get down. In another, a wife must serve her husband, then she can have her food. After a long walk, in ancient Israel, the least of all slaves would wash their feet when guests enter a home. The twelve disciples and the Lord entered the room that was prepared for the Last Supper. Probably, the water, and towel were there, but none to wash. The disciples looked at one another, and thought, why there is no slave to wash their feet? The host has not done a perfect job; it was a significant lapse. (John 13:1-7)
Form of the servant: In that context, the Lord wraps the towel, picks up the basin, fills it with water, and starts washing the feet of the disciples one by one. Among the twelve, one could have volunteered, but none did.
Humility: The service of a slave was a humble task and even a mean job. The disciples thought it was below their dignity and status to do this work. Their honor and prestige would be hurt if they chose to do this job. Nevertheless, the Lord demonstrated that serving others and dirtying hands is not mean, but a noble service. The Kingdom values are at loggerheads with human, cultural, or worldly values.
No competition: There is no competition for such kind of service. The Lord was the lone winner. Why should a highly qualified medical professional, choose to serve the lepers? Those who lived in their comfort zone, go to remote places where there is no running water or electricity to serve the primitive people. The Church has no competitors for service.
Call: God calls His disciples to feed the hungry, give drinks to the thirsty, host strangers, clothe the naked, and visit the sick and those in prison. (Matthew 25:35-46) These are humble tasks, most people like to ignore, forget, and neglect.
Do I serve like my Master?