Rolling bearing failure can not only reveal the failure of a single bearing type, but also can indicate whether the bearing arrangement is reasonable. It should be remembered that the sooner a problem bearing is removed, the sooner the cause of bearing failure can be identified. A prerequisite for the smooth operation of a bearing arrangement is the correct arrangement of operation, environmental conditions and all components in the arrangement (bearings, fittings, lubricants, seals). The cause of bearing failure is not always the bearing itself. Bearing failures due to bearing material and production errors are very rare. Before detecting the cause of bearing failure by testing each bearing component, the possible causes of failure should be investigated according to the methods in Section 2. The operating condition or external characteristics of a bearing can often provide clues to bearing failure. The table in Figure 12 shows the main failure characteristics of rolling bearings and their typical causes of failure. This summary cannot cover all failures but provides a rough outline. It should be reminded that some failure modes are only or almost only found in certain types of bearings or in some special application conditions. In many cases, a bearing will exhibit several failure characteristics at the same time. Therefore, determining the initial cause of failure is often difficult, requiring systematic assumptions of various failure causes. The following system flow is recommended for this case. 11: Failure causes of rolling bearings (source: antriebstechnik 18 (1979) No. 3, 71-74). Only about 0.35 % of rolling bearings do not reach the expected life.