Picture this: you are working on a really long post that you think your readers will love. The post will take a lot of work to get completed, so you decide to break the task in small parts, writing a bit every day.
One day you are working late at a night, and after adding some new paragraphs and images to the post you decide to save it, but instead of hitting the “Save Draft” button you mistakenly hit the “Publish” one.
The post is not ready, it’s not correctly formatted and it’s not even complete, but it goes live anyway. Unless you are fast to think and act there is a chance that the post will be pushed to your RSS feed, and if you are unlucky Google might also be crawling your site exactly at that moment, indexing your half-ready post.
In other words, a disaster.
I have been there, and it’s not a good feeling.
Luckily there is a very simple solution for this on WordPress: whenever you start working on a long post that might take a while to complete, schedule it to some day next year, and then publish it. That way there will be no risk of going live with the post, and once you are ready to publish it you’ll just need to re-adjust the date to the current day.