They fail due dirt and water ingress. If new bearings are fitted with the correct grease then they should last.
Corsa-D - Rear Axle - Wheel Bearing - Noisy Vehicles: Corsa-D 2007-Onwards All Engines Note: Only vehicles with five bolt wheel hubs affected
Complaint: Customer complaints noises from rear axle. Cause: Penetration of water and dirt.
In the event of bearing replacement the seal must be treated with special grease prior to fitment.
Please ensure the entire surface of the seal area is coated sparingly with grease, as shown in the picture I, 1.
(Special Grease - part no.: 09163334/catalogue no.: 19 48 613)