A pair of bolsters is not two identical cushions. Make them identical and one of them ends up with its closing seam facing into the room.
Every bolster has a seam where the cover is closed, and on a shaped cushion that seam is placed at what will be the back or the outer face. If both are made to the same hand, the seam sits correctly on one side of the chair and stares out at you from the other. It is a small thing on a workshop bench and a distinctly annoying thing in a finished room.
So ours are cut as a left and a right. The pattern is turned over for the second cushion, the seam allowance falls on the opposite face, and both bolsters are then set with their closings facing the arms. From the front, the chair shows two uninterrupted damask faces.
On a patterned cloth the mirroring does one more thing: it turns the motif on the second bolster so it leans toward the centre of the chair rather than away from it. Nobody articulates why the pair looks settled. They just do not notice anything pulling their eye sideways.