They established a political system because they believed in having strict control over the kingdom. The Zhou appointed governors to each state. The governors were friends and family, so they knew they would not rebel. The Zhou were comfortable in their wealth, and ignored the needs of the poor which led to the fall of the Zhou dynasty.
The governors asked for more power which also led to the dynasty's ruin. The Zhou dynasty were a clan from the Shang dynasty who were angry with them. And wanted to over throw them. After They took control they established a firm political system. They over threw the Shang dynasty leaders and took their places.