Use Systems Thinking to identify systemic causes of delay, waste, rework, and cost.
Systems thinking recognizes that cause effects are not always direct and linear (like the fishbone or cause-effect diagram might have us believe.) Systems thinking is a way of looking at circular cause effects. In many ways, a systems diagram is similar to a relationship diagram.
QI Macros add-in for Excel contains a systems diagram template. To open the template, click on QI Macros » Diagrams » then Relationship / Systems Diagram.
System Diagram Symbols
Boxes represent key indicators--the number, amount, or quantity of anything that can increase or decrease. (e.g., amount of technicians, number of complaints, rewards, incentives, time on a call, etc.)
Arrows represent the cause-effect links.
Directional labels indicate whether the cause-effect links move in the Same (S) or Opposite (O) direction.
To Create a Systems Diagram
Create a box for each cause and effect. Then link the boxes with arrows indicating "S" for same direction or "O" for opposite direction. For example:
The more pressure there is to "fix" service, the more resources we devote to fixing customer problems (same).
The more resources we devote to fixing problems, the fewer resources we have to devote to preventive maintenance work (opposite).
The fewer resources we have to devote to preventive maintenance work leads to more customer problems (opposite) which ultimately leads to more pressure to fix service (same).
Types of Cause-Effect Loops
There are two basic types of cause-effect loops: reinforcing loops and balancing loops.
Reinforcing loops involve exponential increases or decreases in key indicators.
Balancing loops exert pressure to balance increases or decreases in key indicators.