If the string is bowed, however, the triangle wave is maintained since the bow continues to pull the string to one side at the point of contact. When the point of the triangle shape returns to the bow...If the string is bowed, however, the triangle wave is maintained since the bow continues to pull the string to one side at the point of contact. When the point of the triangle shape returns to the bow it causes the string to break loose from the bow. The wave continues and reflects off the fret end, returning to the bow again, now causing the string to stick to the bow.