I've been kicking around this site for a little while now and I've realized that I'm very rarely even tempted to post a question. I'm an astronomy grad student with a background in physics, so naturally as I go about my life and work questions relevant to physics occur to me; it's one of my main areas of interest, after all. However, I feel like that same background/interests prevents me from actually wanting to post questions here. There is a very limited set of questions that (i) I think of and (ii) I can't reason out a plausible answer to, this is after all what my training as a physicist is supposed to make me capable of... or (iii) I can't find an answer to with a bit of research, another skill I think any self-respecting physicist possesses.
It seems I'm in good company. Most of the top answer authors on this site seem to have a ratio of questions to answers in the range of 1:100 or 1:1000. I wondered if this might be particular to Physics.SE (and other SE's where the topic is one that will naturally attract problem-solvers), and got sort of mixed results. SO's top answer authors barely ask anything, and likewise on Math.SE. Photography.SE, which I'd describe as a non-problem solving based topic, is similar as well. Bicycles.SE has somewhat more even Q:A ratios amongst its top users. Top users from Gaming.SE and RPG.SE ask a lot of questions, and I think I'd describe gamers as keen problem solvers. So hmm, not a lot of support for that hypothesis. It's probably a lot simpler; it's a lot easier to answer questions than to ask (good) questions, especially in the volume required to end up at the top of the rep scale.
Great questions can come from anywhere, and sometimes a simple question that anyone can ask can turn out to be very interesting and complex (my favourite example here is A mirror flips left and right, but not up and down). But a piece of old wisdom goes that the more things you know about, the more things you find that you don't know about. An expert (I use the term loosely, what I really mean in the context of Physics.SE is anyone with about the equivalent knowledge required for a bachelor's degree in physics) should have some advantages when putting together a question, though. They should understand the basic physics underlying the topic, so they can really zero in on the concept they want to ask about. They know where to look for reliable information and can understand and evaluate the validity of whatever background material they come across. And I'm sure there are more reasons. Of course there are also potential drawbacks to being an expert trying to write a question, which I sort of outlined above.
So my question is: Why do you think many clearly knowledgeable users don't ask more questions? Can we/should we/how can we encourage them/help them to ask more? I feel like there may be an untapped wealth of great questions lurking out there.