And one last thing.... .1% seems a little too optomistic. I know that its more than that. If it is less than 1%, it is still a threat; if the number is there, then the threat is there. If the threat is there, then the possibility of damage or harm is there. Conditional statements, my friends.

In old disk models, sudden power interruptions or a power supply failure sometimes resulted in the device shutting down with the heads in the data zone, which greatly increased the risk of data loss. In fact, a manual procedure existed for parking the hard disk heads before shutting down the computer.

To prevent such situation, most modern HDDs, when powering down, move the heads to a landing zone, an area of the platter usually near its inner diameter (ID), where no data is stored. This area is called the Contact Start/Stop (CSS) zone. Disks are designed such that either a spring or, more recently, rotational inertia in the platters is used to safely park the heads in the case of unexpected power loss.