"Only experienced editors should ever create an article from scratch. Others should first create a draft page and build the article there."
And as you say they aren't indexed.
https://en.wikipedia.org/wiki/Help:Userspace_draft
Userspace drafts also won't be deleted for non-notability, and they can be published whenever the editor feels that they're ready.
Neither of the draft spaces on Wikipedia are indexed by search engines, because these staging areas generally aren't proofread by other editors.