Why does this happen?
Classic Flaps have multiple leather panels and a chain that can rest against the bag when closed. If the bag is packed tightly in tissue, inserts, or its box, those surfaces can sit in prolonged contact and “set” into each other. Over time that can create indentations, crease lines, and a flattened quilted look.
Why original packaging can be a problem
Original packaging often looks protective, but it can reduce ventilation. Several storage guides recommend keeping Chanel bags upright, lightly stuffed, and in a breathable dust bag rather than sealed in a box, because leather needs air circulation.
In humid conditions, enclosed storage can also promote mold or white spotting, which then damages the leather further.
Better storage approach
A safer method is to store the bag upright, lightly stuffed to hold its shape, with the chain tucked inside and a soft separator such as felt or tissue between the flaps if needed.
Keep it in a breathable dust bag, not tightly sealed, and avoid direct sunlight and damp spaces. That setup reduces pressure marks and gives the leather room to recover between uses.
Hope you found this helpful. Happy collecting!