This may limit the bearing's lifetime. If everything else is done right (bearing mounted correctly, lubricated, no dirt, correct loading, etc.), bearings ultim

This may limit the bearing's lifetime. If everything else is done right (bearing mounted correctly, lubricated, no dirt, correct loading, etc.), bearings ultimately fail due to high cycle fatigue at the rolling element tracks on the races. Repeated flexing caused by high Hertzian (contact) stress between ball and race makes tiny divots fracture out of the race surface. Particle count goes up, more divots break out...bearing fails. The grooves they put in the races of these bearings will act as stress concentrators and accelerate fatigue failure compared to ungrooved bearings. Still, if low friction is more important in the application than long life, this may be a useful new twist on rolling element bearings.