The little painted medallions on the drawer fronts are composed as a set, not as individual panels, and that is why the drawers are numbered on their backs before they are ever painted.
Painted individually and fitted in any order, a row of medallions looks restless. One has more red than its neighbours, one is composed a little tighter, one has a highlight falling from the other side. Nothing is wrong with any of them and the row still looks unsettled.
So our painter works the whole row at once, laid out on the bench in the order they will occupy. The palette is mixed once for all of them. The light in every medallion is made to fall from the same direction. Weight is distributed across the row - a busier medallion is placed where a quieter one balances it, and the strongest is kept for the centre.
Once the row is right, each drawer is marked on the back with its position, and it goes into that opening and no other. Fit them in a different order and the composition the painter built simply comes apart.