The most important properties which anything can have are those properties that deal with its stability.
In a complex system, negative feedback loops will keep some variables of the system in balance. This stability might be desirable or not.
Most complex systems are "dynamically stable". With enough force it is always possible to topple them.
The problem is that sometimes it takes a lot less force to topple the system than to bring it back to the desired stable state.
Therefore, when acting on systems, we need to act small and observe the consequences of our actions.