It could be that the interaction between the two factors (poor safety practices by an airline and the lack of disclosure by Boeing) increases the risk. Suppose

It could be that the interaction between the two factors (poor safety practices by an airline and the lack of disclosure by Boeing) increases the risk. Suppose that steering in a new car model tends to drift from the straight line slightly more than usual. Attentive drivers would easily correct for it, and would merely find it annoying. For them the accident rate would increase very little if at all. OTOH, the accident rate might go up more noticeably for those who text while driving, since they often won't notice the drift until it's too late. When you look at the accident reports where steering drift was a factor, you'll see that most of them involved distracted drivers.