I was on site recently to do some program changes. Upon opening the cabinet I noticed some odd wiring, and checked the program to confirm... Yep, safety contactors removed from the safety relay and now put on the PLC outputs, feedback from the safety relay on a PLC input and some timers that made absolutely no sense whatsoever in the code. Effectively, they put a TON between the safety signal and the contactors, but the way it was written assumed that one contactor was for E-Stops and one for guard doors.
Moral of the story. We should stop putting E-stops on machines and let the problems sort themselves out. "I might be a commissioning engineer, but I can't fix stupid."