How Can a Hard Drive Shatter Inside, With No Impacts Whatsoever?

"Another day, another replaced hard drive," Chris Cook thought at his tech support desk while unwrapping the unit, fresh from storage. Until he turned the fixed ThinkPad on and heard the weirdest rattling noise ever.

The drive didn't mount. It spun up, but nothing happened. The BIOS didn't show anything and the noise, that horrible rattling noise of a thousand-cockroach horde running viciously through a tin tube, kept roaring. "Something is very wrong here," he thought after trying every trick in the book. It was then when he decided to open the drive on the bench at his Spring/Nextel's tech support office. Voiding the warranty, he was shocked when he found this mess:

"Shattered? How the heck can a hard drive plate be shattered in this way? This is not possible."

The drive was new and there were no visible marks outside. And as you can see in the images, the drive plate shattered on its own. Somehow. There are no signs of hammering or violence anywhere, except for the metal shards themselves. Chris swears that this is what happened and has no explanation about it, except that the 10,000rpm engine of the drive may have gone crazy at one point. I find that unlikely but who knows. Any expert in hard drives out there can tell us how this may happened?

While you think, here's some good music that matches the theme of this post (at least in its title). [Thanks Chris]