They will know which side it is usually, the issue is: if the link is on the bottom, how would they remove it?. They put it on both sides, so it can be accessed if its on either side. Most flippers, for example are mainly used on way up, and if they're upside down, they can be re-righted with a good shove from an arena marshal, but invertible robots tend to be a blocky shape and so require much more effort to right by hand.