I don't believe it's possible to work in IT and not wonder why so many IT managers are clueless about anything beyond report completion and very basic project management. Not all of them, of course; and you have to allow for the data processing people too, because many of those are genuinely expert in their field, but far too many to explain by simple bad luck in hiring.
I think there's a non barking dog type of clue in a quick guide called The Five Essential Phone Screen Questions that I've long admired. Written by Steve Yegge, this offers a concise guide to recognizing the poseurs who respond to web or print ads for programmer jobs.
Mostly I think it's good advice. Thus he talks about keeping the initial phone discussion focused instead of letting the candidate ramble, looking for diversity in experience, and using five simple questions as probes to determine whether a candidate is hopeless or possibly interesting.
Thus he asks them:
Overall the questions he proposes are surprisingly easy, but it's a nice piece of work and worth reading for people on both sides of the hiring issue.
On the other hand, the specifics given in his examples are only applicable to hiring programmers and then only within a process in which pre-screen interviews are conducted by technical personnel and hiring decisions are made by a peer group after on-site interviews.
Think about that process for a minute and you'll see it makes perfect sense - and, in fact, most academic, R&D, and technical consulting posts are filled using this approach.
But here's the point: you don't see this on the IT management hiring side at all. Instead, people from HR or outside consultants, most of whom know nothing about IT, conduct the interviews to generate a short list of acceptable candidates and the final decisions are then made by senior people whose exposure to IT usually consists of little more than reading PC ads in drug store flyers, learning from Oracle ads on the back of The Economist, and unwilling participation in IT crisis and related budget meetings.
Thus the explanatory parallel for IT management hiring, is I think, to putting a committed vegan in charge of the annual Ranchman's barbeque.