Re: Shrapnel...
No, it's a management "I'm not buying a case that costs three times what the computer costs!" decision that ends up with them replacing the computer enough times to make the case a cost effective repair.
I did a contract job back when Code Red and Nimda where the scary monsters of the week, and got a tour of the local aerospace plant when the place had those two bugs burn through their network. We had to have the on-site tech visit most of the machines in the manufacturing area because the Cd drives were trashed from all the titanium and other metal dust, because they were not in a good enclosure. (tl;dr- a milling machine that carves turbine parts out of blocks of titanium costing more than a Cadillac is dead-lined because the ~$30 Cd rom drive in the ~$700 desktop can't install patches and is therefore excluded from the network and the ability to do.. anything.)