There is no appropriate English word for this Japanese. They usually translate it into 'work hard', 'study hard', but this word includes more than it. This comes from the oldest Chinese poetry book, ػСٱ޿( Shikyo eifu kiiku). (Setu) means cutting horn and bone of animal, (Sa) means sharpening it. (Taku) means hitting and breaking a rock, and (Ma) means polishing it. These tasks take long time and require preciseness. In the poetry book, they respect the craftworkers for their extreme precise work. So, in my opinion, the (Sessatakuma) means not only working hard but also improving self, and it is mentioned about the importantance of process. But, in fact, it is easier said than done. I believe that this sort of philosophy is closely related to the old Japanese culture and philosophy.