I have just unboxed a new larder fridge and noticed that there was a dirty black mark on the back, just above the compressor, which then has had a piece of silver tape put over it.
The fridge is otherwise fine and seems to be working, though I'm not quite sure if the (burn?) mark is a sign that it might fail sooner than other fridges due to a fault in the manufacturing process.
An image of the offending mark is on Flickr: http://flic.kr/p/9c87gf