The defective circle was a small, seemingly insignificant flaw in the foundation of the dam. But over time, the water pressure caused the flaw to grow larger and larger, until eventually the dam collapsed, destroying everything in its path.
The defective circle was a metaphor for the many small problems that can lead to big disasters. If we ignore these problems, they can eventually grow out of control and destroy us. It is important to be aware of the potential dangers in our lives and to take steps to address them before they become too big to handle.