I can see nowadays, more than two downvotes on posts of newbies to the site (SE) or instant closure of question. I don't feel one will wantedly ask Low quality posts, either they might lack knowledge about that particular topic or Stack Exchange, confusing with other sites like quora. So, Like @uhoh commented in one of a question, I feel it is a unwelcoming trait, instead we can as ask them to improve their post and then reopen it if the question was closed. What is your opinion ?
Do we need to downvote posts of New Contributors?
No, we really don't!
This is a low question rate site, so we don't need to be in triage mode.
The problem with quick down votes on new users' first questions is that they get discouraged and give up, whereas if we are encouraging and helpful and work to improve the question, they may continue to be engaged on the site.
I shouldn't have to remind folks, but getting new users to be engaged on the site and helping them ask good questions is a good thing!
Also, those down voters will frequently forget to go check back to see if there's been an improvement that would trigger them to change their vote. You can always down vote at a later date. With only a half-dozen questions per day, it is not hard to see yesterday's questions here.
It depends on whether the question can be improved or not.
A question that is just vague or hard to understand, I might leave a comment - I wouldn't usually downvote.
A question that shows no effort, tries to solicit answers for the apparent purpose of assistance with homework or assessment, propagates personal or "fringe" theories or has ulterior motives - I downvote.