Why was the economic system of manorialism used in the early Middle Ages?

The economic system of manorialism was widely used in mediaeval Europe as a mechanism for landowners to lawfully maximise their profits while exploiting a peasant labour.

in medieval Europe, the economic system of manorialism was often practiced as a way in which landowners could legally increase their profits, while taking advantage of a peasant workforce.

c) troops march forward in close formation against newer, more accurate weapons