If we sort questions by vote and go to the last page, one will find many questions with a score of -30.
Why are they kept? Shouldn't they be deleted?
What if you thought of asking the exact same question? Now you are warned not to, since the duplicate is already there. No matter how appreciated or not the question is, it serves a purpose.
And maybe the question has some excellent answers. If a question was downvoted for a lack of effort, being unclear at first, or any other reason, the answers could be useful to future reasons.
Just because a question may have been bad, doesn't mean there isn't some value there. There could be great answers, for example, and deleting that content would deprive people from that knowledge.
And on a Meta site, where feature requests (as well as ill-considered discussions) can attract a lot of downvotes, it is important to keep posts around to show that the community consensus was against an idea. Deleting such posts would only lead to repeated discussions.
On the other hand, if a post has no value for future visitors, or attracts a lot of noise (spam, pointless discussions, flaming, etc.), it should just be deleted.
My question recently got deleted though it had good answers
FWIW - one of those answers was mine.
Your question was not constructive, didn't contain a "question", nor was it a point of potential useful discussion, as you asked nothing, proposed nothing, and simply stated "what is".
I answered to provide feedback, as there was nothing to help you with, and nothing to answer.
As for your attempt here to find some injustice from a -30 question being allowed to remain when yours was deleted, some questions, even though highly downvoted, provide reference and information useful to others.
Without their remaining, someone else might otherwise ask the same question, and we'd be forever answering the same old questions without even knowing it.
Which is just a waste of time.
Your question on the other hand offered no valuable keywords for future reference, and no useful ideas or suggestions.
Even if you didn't intend it to be a rant, it came across that way, as you simply stated a load of negative points about Stack, it's users, and Staff, and some of it was a bit close to the knuckle.