Because you couldn&#x27;t find a meaningful way to assign Chinese characters to represent each possible combination of two of {left, right, down, rotate}, which is what the previous hex encoding mentioned can do, let alone do better.  (As a novice, I can think of relatively reasonable ways to represent some of them, but no way to account for order.  For example, &quot;down left&quot; could be &quot;southwest&quot; via the Zodiac animal, &quot;left right&quot; could be &quot;horizontal&quot;, and &quot;down rotate&quot; could be &quot;screw&quot;... but that wouldn&#x27;t help with &quot;left down&quot;, &quot;right left&quot;, etc.)