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Consider a (total) wear‐out failure of a brake pad on the left front wheel of a car. The local effect is that the braking effect on the left front wheel is strongly reduced and that the brake disc may be damaged. The next higher effect is that the braking effect of the car is uneven and not adequate. The end effect is that the car cannot provide a safe drive and must be stopped.

A general picture of the relationship between cause and effect is that each failure mode can be caused by several different failure causes, leading to several different failure effects. To get a broader understanding of the relationship between these terms, the level of indenture being analyzed should be brought into account. This is shown in Figure 3.6.

Figure 3.6 shows that a failure mode on the lowest level of indenture is one of the failure causes on the next higher level of indenture, and the failure effect on the lowest level equals the failure mode on the next higher level. The failure mode “leakage from sealing” for the seal component is, for example, one of the possible failure causes for the failure mode “internal leakage” for the pump, and the failure effect (on the next higher level) “internal leakage” resulting from “leakage from sealing” is the same as the failure mode “internal leakage” of the pump.

Failure effects are often classified according to their criticality as discussed in Chapter 4.