Articles in Blogless can be tagged as draft:
Blogless always generates static HTML, so your draft article is saved as any other article of your site. But the draft flag says Blogless to exclude the article from any list, where it could appear, like the sitemap, the rss feed and the optional article list at the bottom of your site's index page.
So, finally the draft flag does nothing more than to hide your newly written article somehow. Simply nobody will know, that it does exist.
Example for http Error 404 page
For example you should do that for your "Article not found" page, the http error 404. This page always will show up, if somebody calls a non existing article or url and since it is no real article, it should not appear in any list.
This page's url can be configured for apache for example by making use of the provided .htacces file. For nginx or other webservers you have to do this setting for yourself.