Control and reaction are the default mechanism to reduce uncertainty and unpredictability. In reality, the pace of those two villains just growing. The best way to deal with them is to prepare people to respond.
Unclear roles, responsibilities, and expectations are some of the main reasons for a high level of complexity. When those 3 are not available, people jump to conclusions that end up with confusion and uncertainty.
Complicated and complex are not the same. Each one of them required different thinking and tools to deal with. But, in reality, they both interwoven. This video explains the difference between complicated and complex.
Knowing the level of complexity you are dealing with is key. To high-level of complexity and there is a risk to fall into entropy. To low level and your competitive advantage is at risk. This video describes in high-level how to measure complexity?