They function with techniques of control, manipulation and faulty finding. There is generally a hierarchy with the dominant member on top who dictates to others. Each person has a designated role which they are not allowed to deviate from. Closed systems function to keep the status quo by insisting that new information and change be limited. Dysfunctional behavior and addictions may be present.
Abusive relationships are always closed.
Tightly closed systems are authoritarian in nature where personal freedom and new information are suppressed such as Hitler's Germany, prisons and cults. When we were children we were not able to choose our family system. As adults, we get the systems we are willing to put up with. With all the personal growth options available, individuals can take the opportunity to learn about their behaviors which keep them caught in unhappy situations. When we learn more healthy behaviors, out systems change to reflect the level of our healthiness.