And in the beginning people were vociferous and participative and yay, they did up- and down-vote much! And lo, time did pass, and people became less interested and less attentive, and it did slow down the acquisition of rep and badges thereby...
@L.Dutch is right, the perspective is neither a rule nor a rule-of-thumb (meaning, an "expectation"). That people have commented to that effect in the past is true, however, because voting serves a purpose it's better (IMO) to err on the side of voting than not. And that's true for both questions and answers.
The basic problem is that once you've gained your basic user privileges on Stack Exchange, the only reasons I can think of to keep plugging along with rep are two:
There's some SE swag that gets mailed to you when you cross the 100,000 rep mark. (Per-Stack! Total rep on the network doesn't count.)
A general sense of respect. People are less likely to challenge a high-rep user (and, on the flip side, they're more likely to follow one, too, meaning watch how you VTC).
Having said that, the rules that are important are reflected by the mouse-rollovers and what we find in the Help Center. For the questions the roll-overs read:
(UP) This question shows research effort; it is useful and clear.
(DOWN) This question does not show any research effort; it is unclear or not useful.
Neither of those statements translate to "I like/dislike this question." In fact, it's a bit of a stretch to translate them to "this is a good question."1 What they do is reflect a statement from the Help Center:
Answer well-asked questions
Not all questions can or should be answered here. Save yourself some frustration and avoid trying to answer questions which...
...are unclear or lacking specific details that can uniquely identify the problem.
...solicit opinions rather than facts.
...have already been asked and answered many times before.
...require too much guidance for you to answer in full, or request answers to multiple questions.
...are not about worldbuilding as defined in the help center.
Don't forget that you can edit the question you're answering to improve the clarity and focus - this can reduce the chances of the question being closed or deleted.2
And when we follow the first link in that section, we learn that a good question is:
How do I ask a good question?
We’d love to help you. To improve your chances of getting an answer, here are some tips:
- Search, and research
- Be on-topic
- Be specific
- Make it relevant to others
- Keep an open mind
You'll notice that other than the statement that says "search and research," nothing in those statements talks about the premises or topics chosen by the OP. In other words, a question can be a well-asked question, deserving of an up-vote, and yet be unanswerable. It can also be a question that has a perfectly obvious answer but is so badly asked that it deserves a down-vote.
Above all, remember that the purpose of a frame challenge is not simply to instruct the user about something they don't understand well. We get all kinds of people on this Stack with a wide variety of education, experience, and research skills. What was trivial for us may not have been trivial for them. The purpose of a frame challenge remains, as with all answers, to answer the question. The frame challenge is what adjusts the premise of the OP to allow the answer the respondent believes is correct.
So when we consider the practical applications, if you felt a question deserved to be answered for any reason, why wouldn't you also cast a non-obligatory up-vote? Not as a rule, nor as a rule-of-thumb, but as a participatory preference that supports the whole?
1 And this is important, because how most people use the votes is to express popularity — and even that's complex. Good examples are questions about gender, gender roles, and gender identity. I've seen well-asked questions get down-voted to the point of deletion because people didn't like the question. In other words, hot-potato questions tend to suffer most from inappropriate voting. But, c'est la vie.
2 That last statement, actually found in the Help Center, is dubious because we have an unwritten expectation that no edit shall invalidate an existing answer — and since we have a number of users who will (and do) answer anything fairly quickly, the statement is for all intents and purposes, false. You can't edit a question for any practical purpose other than legibility, grammar, and spelling unless you're lucky enough to catch it before someone answers. Type fast.