URL Removal Tool in GSC Doesn't Actually Remove Pages

In a recent incident where a website was attacked by "Japanese Spam", the owner wanted to know why the hacked URLs were finding their way back into the index after being "removed" using the removal tool in Google Search Console.

As seen below in the response tweeted out by Google's John Mueller, the URL removal tool in Search Console just temporarily hides pages from the search results, it doesn't remove anything from the index...

So, in spite of being "removed" using the removal tool, the URLs remain in the index. This means they can also be displayed in the search results. And that's why non-existent spam URLs are sometimes found in the SERPs.

As explained in Google’s Webmaster Support page...

The Removals tool enables you to temporarily block pages from Google Search results on sites that you own

Below is Google's 8 minute video that shows and explains everything you need to know about removing content from Google's index including the removal of outdated content and permanent removal of content.

• Actionable Strategy — You should use the URL removal tool in GCS only for temporary removal. To permanently remove content from Google's index you must take one or more of the following actions.

  1. Remove or update the actual content from your site and return either a 404 or 410 HTTP status code. Non-HTML files, like PDFs, should be completely removed from your server.
  2. ...