The rationale for the extraordinary wear resistance of multiple-layered (TiN/Al2O3/TiCN) coated carbides when turning AIS11045 steels is discussed. The crater wear rate was drastically reduced with the exposure of Al2O3 layer. When TiCN was exposed, the surrounding Al2O3 still protects the coating. Crater wear accelerated to expose WC causing catastrophic failure after the protection of Al2O3 is gone. Despite of the cracks on the original new inserts, coating delamination was not observed. The observed wear patterns were correlated with FEM-based temperature simulations to determine reasonable friction coefficients. The location of maximum temperature coincident with that of maximum crater wear was seen to progress into different locations as each layer was exposed. Thus, the outstanding wear resistance of multilayer coated carbides comes from the location of maximum crater wear progressing into multiple locations as each layer is being exposed. Flank wear evolution followed a similar trend as crater wear.