Whether you are building your shop on your own, or you have an established business with employees, you will need to give access to your shop to other people at some point. To manage your daily orders, to get some technical help, to work with professional translators, etc.
Whenever you need to give access to your shop to someone, you should create an account for this person (never give your own credentials!) and carefully set the permissions. The team pages will help you with this.