When removed image, his folder still live on the disk

[cleargoal]

I make a method to remove an image.
It looks like

        public function deleteImages(string $imgIds): void
        {
            if (isset($imgIds)) {
                $deleting = explode(',', $imgIds);
                foreach ($deleting as $imageId) {
                    Media::find($imageId)->delete();
                }
            }
        }

As you can see, I used the ->delete() method described in docs.
I checked its functionality by deleting the image with ID 15.
The result can be seen in the screenshot:

• in the table, there is no record with ID 15
• but on the disc, there is an empty folder '15'
  

Is it correct behavior?