In a classroom, you finish your worksheet and wait for the signal. The teacher calls for homework, and papers pass hand to hand up the rows.
Your sheet reaches the front. The teacher collects the stack, straightens it, and slips it into a folder on the desk. The page shows your answers, but nothing else—no scores or marks appear at that moment.
Weeks pass. New lessons fill the days, more assignments come and go, but that folder stays put, the papers inside unchanged from view.
One day, the teacher passes around a pile of sheets. Yours comes back with a circled number at the top, checks beside right answers, and lines of notes. The results stand out clearly now.
Handing in the homework set the paper aside. During the weeks out of sight, the outcome formed on it. Time held the change invisible until the return made it plain.