Your understanding of what is difficult is wrong because you&#x27;re looking at it as a detection problem when it&#x27;s actually a false positive problem.<p>See: <a href="http:&#x2F;&#x2F;laughingmeme.org&#x2F;2011&#x2F;07&#x2F;23&#x2F;cost-of-false-positives&#x2F;" rel="nofollow">http:&#x2F;&#x2F;laughingmeme.org&#x2F;2011&#x2F;07&#x2F;23&#x2F;cost-of-false-positives&#x2F;</a>