We hope you will not use a blank document to start each document you create in Word. Instead, you will typically launch a document using a template that has some or most of your work completed already, such as a memo template, a report template, a collections letter template, an RFP template, etc.
However, there will be occasions when you will want to use a blank document, specifically:
When you are creating a "quick and dirty" document that doesn't require much in the way of formatting or automation.
When you are creating a new template.