This is what i know, a turbo spins at over 90,000 rpm. Not to mention the fact that 1,300 degree exhaust is blowing over the exhaust turbine. If you turn off your car after running it hard, oil can turn solid from the heat around the turbocharger. You have to idle your car for a few minutes to let the oil circulate and cool down the turbo. People usually dont do this or dont want to wait. A turbo timer wires in to the ignition to keep the car running for a few minutes (user-defined or automatically calculated) to allow the turbo to properly cool down.