Patton argues that places considered too difficult or impractical to use may receive less defensive attention precisely because an opponent assumes they will not be chosen. A route, crossing point or position judged “impossible” can therefore become attractive if that assumption has led to weaker preparation or fewer troops being assigned to it.

The idea depends on recognising how expectations shape defence. Strong positions are often protected because they are obvious avenues of attack, while difficult terrain may be watched less closely. Patton’s approach was to look for opportunities created by those assumptions and to consider whether the practical difficulties could be overcome. The quotation therefore reflects a preference for surprise, indirect action and exploiting neglected weaknesses rather than confronting the strongest defences by default. It also implies that assessments of what is possible should be tested against actual conditions rather than accepted simply because a particular course appears unlikely.