i think someone cut it :o, he will have to go on the plank.
When the wind is not pushing the sails, ships rely on the triangular sails on the back, and rotate the square sails at an angle to get some propulsion. If you sailing with the wind, they sail with with the square sails. Mostly, you dont see rectangular sails at a 0 degree angle. Its just nearly impossible yet complicated to build a 45 degree sail.