It is one of the most common habits of those who play with Nintendo 3DS regularly that they use a cartridge that makes the game more lively and easy to play. Obviously, this cartridge is one which is a foreign body and one that is most of the time pirated. While for those, who are not interested in piracy or related issue, it is a cool device but it is harmful in cases where the question of the gaming device comes into place.
And that is why the company has made sure that they come to know as soon a pirated device is used on them. In Japan they have even disabled any kind of use of 3DS illegal games on it. As soon as such a device is used, Nintendo completely shuts down the system. Updates related to the issue are made automatically.
Nintendo has also made sure that each and every retailer knows in Japan that such a bricking is taking place and that they won't be buying into such systems that have shown a past record of use of pirated equipment.