The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair.
“As an artist, you dream about accumulating enough successful music to someday do just one greatest-hits album, but to reach the point where you're releasing your second collection of hits is beyond belief.”
“No, no, it is obvious that the ECU should act as a close alliance for the benefit of chess.”