Wrong angles

Here's another mystery tie: it's silk, and was made in Italy, but I have no idea by whom. Its right angles are 45 degrees out of sync with the shirt's right angles, hence "wrong angles." But with a tie so festive, who cares?

Why do so many ties have diagonal designs? Ah, there is a good reason: the pattern is usually woven or printed horizontally on a roll of fabric. But in order for the tie to hang properly (i.e. not twist around from the torque of the knot and display its backside), the tie material is cut out of the roll at a 45-degree angle, or "on the bias." And thus the pattern is tilted, and thus endeth today's lesson. Class dismissed.