Brainstorming possible reasons (contributing factors) in each category that could be responsible for the problem is the next step. It may be helpful to place ideas on category ribs as they are generated. In our example, "People" was identified as one category that might have affected productivity in July. Figure 3 illustrates several ribs identified by the team as possible contributing factors to the "People Category". These are quite general possible factors and require more investigation to narrow down the problem. As the factors are listed the team needs to be asked why that factor is present. The team may decide in this process that some possible contributing factors do not apply. Once a specific most likely cause or causes for the problem are identified by the team deeper causes need to be added as additional ribs.
