As I don’t like the COSO risk appetite / risk tolerance approach, I thought that I would see how ISO 31000 approaches these issues.  Better, perhaps, but not much.  These approaches might be fine when addressing the possibility that a product or a part in a product might fail in a limited or acceptable number of instances or products resulting in non-serious or non-catastrophic injuries or damages. The evaluation is different, however, when the consequences can be or are serious or catastrophic.  Suggesting to the public or a jury that even a slight chance of serious or catastrophic injuries or damages is problematic, of course.