I don't think I need to dig around to find links to back me up when I say that some people just have trouble asking their question in the right place, regardless of there being info to the right giving a little guidance; haste might get the better of them, some legitimately might not see it, quite get that it doesn't apply to them, or just blindly ignore it or whatever.
A lot of these users are new, and I think we can provide them more information off-hand.
Once a member of the site and hanging around enough to start flagging / closing questions as off-topic, you find you'll get a bit more information than that new user about to ask a question in the wrong place - it gives a less terse but more assertive expression of the topic (programming? / programming!). It also lists predefined migration routes to sites that we might see fit to ship their questions off to (which they could know nothing of at all).
I suggest the Ask Question page provides the new user this information upfront by incorporating the off-topic dialog content to some extent, allowing at least certain categories of 'confused' users to cut out the middle-man, so to speak.
I've depicted a mock-up below which adds this but doesn't alter the current info box in any way, however, I would think that if this was to be implemented then it would be integrated into one box, or something else, to remove repetition.
A further possibility, since all sites will eventually have appropriate migration routes(?), this could be considered for the engine in general, as opposed the Stack Overflow specifically.