What is the advantage of a closed circulatory system over an open one?

All complex and evolutionarily developed animals, including humans, have a closed circulatory system. This type of circulatory system offers a number of benefits. Less blood is required to provide the body with oxygen, since all blood is in constant motion. It also allows oxygen to be transported and carbon dioxide taken up much faster. With an open circulatory system, some of the blood in the body cavity does not change for a long time. Also, the closed circulatory system allows nutrients to be transported quickly.