In this case, the defect rate that is reported below all the factors is estimating the same quantity, the rate estimated for the overall simulation below the histograms (that is, if you clicked the Simulate button). Because each estimate of the rate is obtained in a different way, they might be a little different. If they are very different, you might need to use more simulation runs. In addition, check that the range of the factor scale is wide enough so that the integration covers the distribution well.

The mean and SD are updated when you change the factor distribution. This is one way to explore how to reduce defects as a function of one particular factor at a time. You can click and drag a handle point on the factor distribution, and watch the mean and SD change as you drag. However, changes are not updated across all factors until you click the Rerun button to do another set of simulation runs.