1. Production process: During the manufacturing process, if parameters such as bottle mouth temperature and pressure are not fully controlled, wrinkles may appear on the bottle mouth during cooling or solidification. This may be an unavoidable phenomenon during the production process.

2. Bottle cap or sealing problems: Using inappropriate caps or sealing methods, or applying excessive force when sealing, may also cause wrinkles on the bottle mouth. This may be caused by improper operation or a mismatch between the cap design and the mouth of the bottle.

3. Extrusion during transportation or storage: During the transportation, loading, unloading, or storage of wine bottles, if they are subject to external pressure or extrusion, it may also cause wrinkles on the bottle mouth. This may be due to improper operation or inappropriate logistics environment.