I feel these answers present a danger to a beta site that is struggling with its scope.
There's a common tendency to see a collection of answers heading off the rails and say, "these answers are the problem - if it weren't for them, things would be fine here." Familiar examples include:
- Subjective questions attracting polarizing, opinionated answers
- Poorly-researched questions attracting poorly-explained answers
- Broad questions attracting scattershot answers
- Extremely popular questions attracting tangential answers
Look around on other sites, read through past meta discussions, and you'll find countless examples of these, along with dozens of proposals for stricter or more elaborate answer-moderation schemes. They all have one thing in common: they don't scale.
Exceptional vs Routine
Stack Exchange is built on the understanding that the vast bulk of moderation is handled by the community at large, the enormous effort broken up into tiny little pieces and spread out such that no one shoulders the bulk of the load. Moderators - the elected or appointed members with the little diamonds next to their names - handle the exceptional cases where the work can't easily be broken up.
Moderating answers should be something you can break up:
It should be trivial for the core membership of a site to look at any answer and quickly determine whether it actually attempts to answer the question or if instead it is merely a reply, spam, or utter nonsense.
It should be feasible for subject-matter experts to review answers to a question and determine if they are accurate and useful. And even when that doesn't happen, it should be possible for the asker and others sharing the same problem to decide which answers are helpful in solving their problem.
...But this all falls apart when you start trying to make up for the deficiencies in questions with additional requirements placed on answers. That is, when an answer can be both accurate and useful in solving the problem and yet still be inappropriate for the site, it's no longer possible for the community at large to moderate answers - you have to rely on Moderators. For every. single. question.
Which transfers moderators from the role of exception-handlers into that of dictatorial gatekeepers.
Don't be blind to the root problem
Years ago, I moved into a place with an ancient refrigerator, and quickly found that I couldn't keep anything fresh in it for more than a day or two. Milk went sour; vegetables rotted; meat spoiled. I could keep things longer by carefully packaging them before refrigeration, but this quickly became a burden. At first glance, the fridge looked fine - it was clean and well-maintained - but it was sick; it had been left unplugged and unused for months at some point in its past, and there were things growing in the insulation.
I could've spent the next year throwing out a lot of food or carefully hermetically sealing any food I wanted to keep... Or I could fix the root problem. Guess which route I chose?
Don't waste your time - or the efforts of those who would contribute their knowledge here - by blaming answers while ignoring a "sick" question.
How to evaluate questions on LifeHacks
I wrote about this before, but I'm afraid I left folks a bit unclear on what exactly I was recommending. So I'll go over it again:
... a question asked here must fulfill two requirements:
It must be a clear, specific question on a practical topic. The asker must communicate specifically what he's looking to accomplish, what the constraints are, what research he's already done, etc. - in other words, all the usual advice for asking a good question applies first - if it's not a good question, it doesn't matter if it's on-topic or not (and in fact it may be impossible to determine).
It must implicitly demand an unconventional solution. What, specifically, "unconventional" means is up for debate, but it's pretty obvious when someone isn't looking for one. Fixing floors and household appliances are ordinary HOWTO tasks; indeed, there are professions dedicated to them. Whether or not there exists a Stack Exchange site for professionals in these fields, simply learning a new skill is not a Life Hack.
Now, here's the punchline: if a question fully satisfies #1, we can often just assume that it satisfies #2 as well! Unless something in the question prohibits unconventional answers, we can just go right ahead and provide them; if it turns out the asker forgot what site he was on and wanted a conventional solution, then he's free to go ask somewhere else.
I followed this up with the line, "we must guard against the temptation to provide conventional solutions to ambiguous questions" which apparently some of you took to mean "go downvote conventional solutions" (even though I did clarify this in the comments). But that's insane: if an asker presents a problem, someone else provides a conventional solution to it, and the asker is satisfied with this solution... Then it's not the answerer's fault that this isn't a Lifehack question! What you have to guard against here is the temptation to keep around every question that gets an answer, even if it becomes apparent that the asker does not want - and the problem does not warrant - a hack.
Conclusion: evaluating your answers
Your two examples are somewhat different:
The first is an answer to a question that clearly defines the problem: how to quickly destroy paper documents without tearing or shredding them. The top answer ably does this by suggesting burning or soaking, although it also suggests two alternative ways of shredding that will probably not meet the asker's needs. Therefore, its only fault is that it is more comprehensive than it needed to be (and also that it distracted you with a picture of scissors).
The second answers an ill-defined question about keeping soda fresh. It's too broad (the question explicitly asks two related questions at the start and then expands the scope again near the end) and the answer does not come close to answering it satisfactorily.
There's no particular reason to criticize the first answer. If you're going to criticize this answer, you should criticize it for failing to satisfy an unrealistic request - and then you should shut down that request (which I've now done). Note that the most problematic answer was a direct response to a problematic question - if y'all hadn't ignored the root problem there, the answer would've been a non-issue.
For more discussion of the various strategies for answering questions here, see: What should a good Lifehacks answer look like?