Can we please STOP closing and deleting old posts with answers?

Question

This is a follow-up for a recent questions of mine:

What are the merits, if there is any, of deleting (correctly) answered questions in the main site of MSE?

I have noticed recently that quite a few old questions with good answers are being closed and deleted (mostly initiated by a same user):

• Diophantine equation $15^x+8^y=17^z$.
• Prove that: if G is simple with n vertices, which doesn't have a triangle and min.degree > 2n/5, then G is bipartite.
• Proving solutions in N
• Show that $ (n+1)(n+2)\cdots(2n)$ is divisible by $ 2^n$, but not by $ 2^{n+1}$
• If $a, b, c$ are sides of a triangle, prove that $\frac{a}{b+c-a} + \frac{b}{a+c-b} + \frac{c}{a+b-c} \ge 3$
• How to prove this logic?
• Is there a proof of infinitely many primes p such that p-2 and p+2 are composite numbers?

I do not see any merit for closing such old questions: who the heck do we really expect to come back and "provide additional context" for a question that was asked two or even six years ago? The further strong action of deletion mostly, if not completely, erases useful information that people created (with valuable efforts and time) together in the main site.

Can we please STOP closing and deleting old posts with answers?

A related post on meta:

• Deleting questions with answers (by a former moderator)

Answer 1

Thanks for saving me the time to post the exact same question. Let me just add my own examples to the list. My inclusion criterion is "contains a neat proof", which may be more liberal than yours, but I am pretty sure that you will find something worthy of preservation in the list (temp mirrors included if you are not a 10K+ user):

• If $a^{2} \mid b^{2}$ then $a \mid b$ (temp mirror)

• Show that $OX=OY$. (temp mirror)

• How to prove by induction that $A = \left\{n \in\mathbb N | n=\frac{(a+b)(a+b+1)}{2}+a \land {a,b} \in \mathbb N\right\}?$ (temp mirror)

• Show that $OB=OC $ (temp mirror) (this one has been referenced in Are points H, M, K' collinear? )

• How to represent an arbitrary real number in $[0,1)$ (temp mirror)

• In a quadrilateral ABCD ,which is not a parallelogramm. On the rays AB,CB,CD,AD we put... (temp mirror)

• How to find $a_n=?$ $(n+1)a_{n+2}-na_{n+1}-a_{n}=0,a_1=1, a_2=0$ (temp mirror)

• Finite dimensional von Neumann algebra (temp mirror)

Answer 2

As quid already remarked on the closure aspect of this meta question, let me address deletion (being aware that this might not make the answer popular):

The further strong action of deletion mostly, if not completely, erases useful information that people created (with valuable efforts and time) together in the main site.

The key word of dispute in the above sentence is "useful". Let's make some statements:

• Every question is useful.
• Only questions fitting the good question FAQ are useful.
• Questions with good answers are useful.
• Sufficiently old questions are useful.
• Popular, highly voted questions are useful.
• Questions consisting of only an image are useful.
• An eager OP makes a question useful.
• Only questions with pristine Markdown and $\LaTeX$ formatting are useful.

Everyone, depending on the assessment of these statements, has a different understanding about which questions are "useful".

Therefore it does not surprise that some users are of the opinion that questions they deem sufficiently lacking in "usefulness" should be deleted. The fact that this meta thread arises (and many before it) proves that there is a wide variety of interpretations of this word "useful".

And since neither side of the spectrum is going to convince the other, our job as a community is to find a proper balance on the spectrum. (Closing-not-deleting might be a part of this.) Just like we managed to create the good question FAQ.

As long as the self-righteousness of both sides continues to prevent a compromise, we are not going to get somewhere. Talking about "valuable efforts and time"...

Answer 3

To almost equate closing and deleting for old questions is not a good idea for this discussion.

Regarding closing the following aspects are important to keep in mind, in my opinion.

• New users might often get to know the site via stumbling over existing (old) content when searching the internet for information. If there is no indication on the old content that currently it could face push-back, it is not unreasonable that they simply mimic they style of the content they saw when asking a new question. Even if the old questions is never improved, the question being closed might guide new users behavior.

• The meta-question here asks:

  I do not see any merit for closing such old questions: who the heck do we really expect to come back and "provide additional context" for a question that was asked two or even six years ago?

  Let's turn it around. What's the problem with the question being closed? It only prevents new answers. Now, let us be realistic, how often does it happen that a new answer appears much later that adds something substantive (especially on the more routine type of questions that are very common on the site)? Even if it is given, how much attention does it get?

Granted, for deletion the balance might be different.

Answer 4

Attempting to outline my thinking. Not sure how mainstream my views are, so feel free to vote/comment as you see fit. As always, I may have overlooked something.

1. I downvoted Jack's question because the title is too sweeping. If adopted as a policy, and taken literally, this would be turned into a tool prohibiting all community control on content quality of past posts, and I find that unacceptable. It is possible that I misinterpreted his goals. But given the recent history of his posts and the literal way some users want to apply "rules" like this I cannot support the general proposal.
2. However, this time Jack, IMO, collected good examples that certainly make a strong case for criticizing the large scale deletions. With the exception of "How to prove this logic" thread, my first instinct would be to keep the question visible (not taking a position whether they should be closed, mainly discussing deletion here).
3. The reason is that, in my opinion, the undesirable content mostly consists of A) homework, B) duplicates. These I will ever tolerate only grudgingly, and seek to close/delete at the slightest excuse. Yes, there is room for compromises (which is why the rules on PSQs/context were formulated).
4. I acknowledge and support quid's "broken window" -argument. Therefore I won't argue in favor of reopening most of these threads. However, I don't whole-heartedly support deletions unless the question is an uninteresting piece of homework and/or covered many times on the site already. Actually, I would even welcome a new answer of the "$p-2$ and $p+2$" question that does away with the need to call upon Dirichlet's theorem. I may exercise my option to post that as a new question, but IMO such an answer would organically belong to that thread :-)
5. A reason for me not to vote to delete an older post is that the deterrence effect is simply not there. The threat of deletion never stops users not interested in rep points from answering, it is only a stronger signal of disproval to them (which is the chief reason for deletions anyway). In those cases when a user is playing the rep game, it does serve as a deterrent also. But remember, deletion does not cancel the rep points, if the post earning them has stayed undeleted for 60 days. Because deletion is different from closure, in the case of an older question it should not (in my opinion) be the nearly automatic follow-up to a closure as is the case with low quality new questions.
6. This (lack of need for deterrence) has also affected my voting when checking out review queues. I used to think that review queues mainly function as a way of collecting questions that need to be closed urgently. I can usually fill my daily quota of votes-to-close by reviewing new questions alone. Therefore I felt that I would get more bang for my votes by skipping old questions while reviewing. I would only come back to them, if I find the time (using CRUDE makes that easy). But, closing an old question is never urgent. Nevertheless, I am re-evaluating my position here while trying to absorb quid's recently posted guideline.

Don't know if I reached any kind of a conclusion? May be just another call to judge things case-by-case?