Garment dyeing, in this case, refers to dyeing the color of the jacket after it has been sewn from white fabric.
By doing this, the uneven texture of the jacket, where the color is slightly blurred depending on the parts, and the puckering of the seams (a drawn-out bite) are emphasised, and a jacket that looks familiar even though it is new is completed.
Of course, just dyeing a jacket in the dark is not enough to make it look good.
It is pretty difficult to create the desired atmosphere.
If it is too uneven, it will look dirty, and if you don't consider the balance between the fabric and the sewing, it may tear after dyeing.