2.7 Multiple-cause diagrams
As a general rule, an event or outcome will have more than one cause. A multiple-cause diagram will enable you to show the causes and the ways in which they are connected. Suppose, for example, that you were asked to explain why a work group was under-performing. You could use a multiple-cause diagram both to help you to construct the explanation and to present it.
Figure 16 presents a picture of the problem. The eye can move from one element to another and can see the connections between the elements. From that point of view, a multiple-cause diagram is rather like a road map. If you can look at the diagram and say ‘I can read that diagram, I can see how it explains the underperformance of the work group’, then the diagram will have been effective as a means of exposition. If the diagram has been effective, then a similar one may be equally effective in explaining an event or outcome.
Using a multiple-cause diagram will help you to think about a problem, to explain the problem to other people, and to decide what to do about it. It will expose the connections between the events (including the loops – the occasions when one event leads to another which, in turn, reinforces the first). It will show you the possible routes into the problem. It will remind you of the complexity of the problem and it will help you to guard against taking an inappropriately narrow view of it.
As you construct and revise a multiple-cause diagram you will be reaching your own view of the problem. If someone else studied the problem they would probably draw a diagram that differed from your own. Different views, or different understandings, of the nature of a problem mean that there will be different ways of handling the problem.