Diligence in study is like a seedling rising in spring, but you will not see it growing with each passing day. Studying is like a sharpening stone. If you don't see the damage, you will lose some money.

Attached translation: Diligent study is like a seedling in spring. You cannot see it growing taller, but it grows taller as the days go by. Failure to learn is like a sharpening stone. You cannot see its losses, but in fact it is losing money day by day.