Lets say you have servers that manage traffic lights , fail an update and traffic chaos that "might" cause an accident that someone dies in. now yes if traffic lights fail then normal road rules apply , approach intersection with caution etc
... but still... MS patch = Death and destruction .....
but if all it costs is money .... patch patch your might machines.
Ask a simple question, will this patch cost lives if it is applied. If the answer is no then apply the patch. Justification of applying the patch , no people will die if the patch is applied.