In systems, feedback structures produce patterns of behavior made up of the events we experience. Unless we understand system structure it's very difficult to determine what actions to take and which policies to adopt in order to positively affect system behavior. Instead of addressing fundamentals, we apply band-aids.  When band-aids don't work, the prevailing "common sense" is that it's obvious we should do nothing.But common sense "derived from experience" is inadequate for addressing the problems we face.