They are best able to show the tracks of the artists 'thoughts. But because most artists are only willing to exhibit completed works, these rough sketches are very difficult to obtain.
謝里法指出，從草圖最能看出畫家思考的軌跡，但限於一般畫家都只肯展出已完成的畫作，不願將草圖示人，因而取得不易。