It's just that for those of us dealing with scale, for those of us tasked with keeping people safe, we have to assume the worst will happen, because for us, a one-in-a-million chance is pretty good odds.
因为我们要应付安全风险， 我们承担着保证大众安全的责任， 我们必须假设最坏的事情会发生， 因为对于我们来说百万分之一的几率 是一个非常大的可能性。