A unique email address sets you apart.
Email is an essential form of communication in the world today. Not only is an email address important, but the correct structure of your business email list will give your recipients a clear indication of which area or department they are dealing with. And if you choose to use your email address for a personal reason it can be simple.
Many people use gmail and others that market and brand Google, that why you use the gmail domain (@gmail.com). Having your own domain instantly sets you apart from this and is more professional.(@your-own-name)