The biggest down fall of a turbo is the driver. By that I mean how many of the get in the car to go from a to b really know how to treat a turbo engine. The death knell of a turbo is when you shut down the engine before the turbo spins down. Like one might do when pulling into a motorway fuel stop. Or jetting off just after starting a cold engine. It's one reason I would personally never buy a used turbo car. It would be a huge benefit if makers of turbo engined cars were to include pre-post oil delivery to the turbo bearing to prevent oil coking.