I noticed that it became common to see newcomer posts with negative votes, and no comments to explain it. 

Sometimes i even wonder why some good questions get downvoted without reason.

Is there a way to add something like : 

* <strike>first downvote for a newcomer post requier a comment.</strike>

* Adding for a new user post an automatic feedback on a downvote pointing to the help to explain which mistake has been made in the post (maybe a with a popin message option, to be even more accurate)

thanks for reading.