Its purpose is for destroying your computer as the police are bursting in through the door but the hard drive contents will most likely be retrievable. It will hence be used for spiteful revenge attacks which makes the sellers and designers low lifes as far as Im concerned.
If you did need to wipe data, you can certainly wipe most of it by running a magnet along it in one direction several times or by placing it in a microwave oven (I think). All storage is metallic in the computer and flash's index can be corrupted with magnetic fields. So the question is, is your motherboard one with sensitive data on a ROM, etc?
The motherboard is the main circuit of your computer. This aims to attack the motherboard but is said to leave ALL storage mediums unharmed and the CPU. 
