I think the picture might be a little misleading depending on the manufacturer, the finished face may show the horizontal pieces glued jointed the whole vertical way only, but underneath it is glue jointed horizontally also throughout, this I found out by looking at the unfinished back side of the board, or if you cut the top layer off you can see how the inside is jointed vertical and horizontal, how ever the finished top layer if not jointed horizontally can be used if thick enough. I think the vertical is still better for strength and performance.