In the last few decades a vaguely defined science of complexity has come to be widely recognized as important in many areas. Some trace its origin back to a lecture, Science and Complexity, given by Warren Weaver in 1948,
in which he identified organized complexity as distinct from disorganized complexity. Complexity has been studied in many different contexts—mathematics, communication, systems analysis, cognitive psychology, etc. Complex systems are found in all these places and more, which is what makes it difficult to define complexity as a discipline: it's simply too complex to permit clear definition.
One unsurprising characteristic of complex systems has emerged from studies that provides insight into current problems and which even might be taken as an axiom of complexity: complex systems are unstable and almost always fail, in fact, they may routinely run in a failure mode. Here is an interesting outline on the subject of the failure of complex systems:
Examples abound. Financial transactions on Wall Street have become so complex that no human can follow them in real time, hence the risk of financial crisis when several things go wrong at once. Electronics are now incredibly complex allowing hackers to sabotage systems which are thought to be well protected. Climate change is the result of many different processes resulting in unexpected and sometimes disastrous outcomes. Even human physiology is a complex system with frequent breakdowns. Even your ordinary laser-reading CD player produces good sound only because it comes equipped with error correction codes.
I keep saying the old phrase, "Keep it simple, stupid" - KISS. But everyone loves the bells and whistles and gadgets and gizmos, to the point where it's hard to figure out how to make a phone call. When, on the ancient old hand-dial land-line phones, you just dialed a number and someone answered, or didn't.