Part of the problem of mixed system is lack of intuitions.
I grew up in the metric system, so I still struggle with intuitions from imperial systems. (It&#x27;s very hard for me to &quot;feel&quot; 10 feet, while I have an instant feel what 3 meters is like.)<p>Most cases, this won&#x27;t cause issued beyond missed perceptions, but it can hamper the ability to detect anomalies -- perhaps part of the reason what caused some of the incidents described in the article as well.<p>Long ago, I once overheard someone&#x27;s conversation, this was an architect in the process of designing a home for foreign market, and he was designing closets in some room too small, again, because he had to work with obscure units (for Japan, they use &quot;Tsubo,&quot; about 3.306 square meters &#x2F; 35.58 square feet -- and yeah, this is one of the few places that Japanese people are still stuck with customary units...)