I have no information as to why, but I can take an educated guess. At the presentation I heard Eric say that the mechanism for the rings was engineered very simple and the best solutions are most often the simple ones, not the complicated. And I agree. And the beancounters agreed, because it was simple and fairly cheap to make, so it fitted the BOM
Except it was probably so simple that it could not withstand the very nature of a pinball machine. And to make it pinball proof it had to get a lot less cheap. Again, that is what I have made of it and I really cannot see it otherwise. I refuse to believe that the guys at JJP like Eric would not be ABLE to make this work, just not in a feasible way.
What does bother me is that they do pin it on the engineers. Again, I may be way off here, but I feel this is not an engineering problem.