- Faster to Edit
For simple edits, it is often faster to make changes to a page using a text editor.
- Helps You Learn HTML
Text editors teach you to read HTML. They often have wizards and functions to do the more common tasks (like the basic page tags), but you'll learn HTML if you use a text editor
- More Marketable
A Web Developer who can write HTML using a text editor will be more marketable than one who can only use a WYSIWYG editor. The former is more flexible and can get up to speed on any HTML editing tool, while the latter has to start all over with each new editing tool.
- No "Funky" HTML
The only HTML that will be in the document will be tags that you placed there deliberately. This will help your pages download faster, as well as look leaner.
- Human Readable HTML
This is especially important if you work on a team of Web developers. The HTML can be spaced as your team likes it, and include comments and other notes to allow more efficient editing by other team members.
- Must Know HTML
While most HTML text editors can help with tags and suggest attributes and so on, this is no substitute for knowing HTML. Most modern text editors have drag and drop styles such as bold and italic, but if you can't remember the code for "non-breaking space" your editor might not be able to help.
- Steeper Learning Curve
Because you have to learn both HTML and the editor functions itself, a beginner will find a text editor more difficult to use.
- Harder to "Design" With
Some people find text editors more difficult to design pages in because they can't visualize how the page will look from just the HTML.
- For Professional Web Developers and Advanced HTML Writers
If you want to make Web Development your profession, and you don't plan on opening your own Web Design studio, then I would recommend learning HTML and using a text editor. Text editors will get you farther in the long term, as they will reinforce your knowledge of HTML.
- For Beginners and Non-Professional Web Developers
If you want to do Web Development as a hobby, there is no reason not to use a WYSIWYG editor. But remember, to get a job as a Web Developer, you really do need to know HTML, and a WYSIWYG editor will not help you there.