I wanted to spin a Cabled 4-ply yarn. (It's supposed to be great for knitting socks.)
All I needed to do was take two 2-ply yarns and ply them together. Simple.
The yarn I created was over-plied - which is good - and the yarn was very energized. I figured wet-finishing would calm it down and - yes - some of the energy was released but the yarn still did not look right.
I checked my Spinning reference books. Oops.
I was supposed to change the spinning direction of the second ply. That is, the last ply was supposed to be spun (Z) clock-wise, to the right, the same direction as the spun singles.
Instead, I had spun Z + S + S.
Cabled yarns are correctly spun: Z + S + Z or S + Z + S.
Instead of a Cabled yarn, I had made a Hot Mess.