The seamstress shortens the dress or skirt to the desired length, leaving the seam as it was originally. Let the seamstress know in the comments if you have any special requests. By shortening the hem according to your needs you will be more likely to wear and rewear your garment. You can also consider shortening the hem when you are altering the garment for a new style.

Extending the life of a garment is always worthwhile. The longer you wear a garment, the lower its environmental impact and carbon footprint.
By choosing to repair your clothes instead of buying new ones, you're doing your bit for more sustainable future - congratulations 👏