Not an expert but I'm acquainted with someone that builds high vacuum stuff for physics experiments. Cold welding is an issue. Essentially if two sufficiently c

Not an expert but I'm acquainted with someone that builds high vacuum stuff for physics experiments. Cold welding is an issue. Essentially if two sufficiently clean metal surface come in contact in sufficient vacuum, they weld together without any heat or liquefaction. So if you had conductive metal dust shavings contaminating the sat, once it's in space they may find their way to a spot where they can create a short circuit. Apparently the welds behave pretty differently from ordinary welds like allowing movement.