Word processors offer several advantages over HTML-specific authoring tools.
Users are comfortable with word processors.
Your word processor gives you a single tool to do it all. There are downsides, though. And because word processors don't use HTML as their native language, everything must go through a conversion process. Commonly you'll see that details like table borders and certain text enhancements do not translate properly. Also, none of these programs can break a long word processor document into multiple HTML pages based on user-specified criteria, such as chapter and section breaks or heading styles.