The recycling of oceanic plates by means of subduction represents the major plate driving force and subducting plate strength controls many aspects of the thermo-chemical evolution of Earth. Regardless of its prior history, each subducting plate experiences intense normal faulting1-11 during bending that accommodates the transition from horizontal to downward motion at the outer rise at subduction trenches. Here, we investigate the consequences of this bending-induced plate damage using new numerical, thermomechanical subduction models in which both brittle and ductile deformation, as well as grain size evolution, are tracked and coupled self-consistently. Pervasive slab weakening and pronounced segmentation can occur at the outer rise region due to the strong feedback between brittle and ductile damage localization. The “memory” of bending varies from segmentation to broadly-distributed damage depending on the age of the subducting plate, mantle potential temperature, and the magnitude of strain-induced weakening of outer rise normal faults. This new slab damage phenomenon explains the development of large-offset normal faults8,9, the occurrence of deep compressional thrust-faulting earthquakes12, and the appearance of localized areas of reduced effective viscosity13 observed at subduction trenches. Furthermore, brittle-viscously damaged slabs show a strong tendency for slab breakoff at elevated mantle temperatures. Given Earth’s planetary cooling history14, this implies that intermittent subduction with frequent slab breakoff episodes15,16 may have been characteristic for terrestrial plate tectonics until more recent times than expected from memory-free rheologies17.