Because that's not all I want to know. I want to see the first things that surface in their mind and what they enjoy talking about. It's not a trick question and the only wrong answers are very clearly wrong sometimes even to those who don't work in software.
> Hiring managers frequently can't differentiate between people who are knowledgeable and people who are just good at interviewing.
I don't agree with this at all. We don't have "hiring managers". That's the problem right there. What the hell are they going to know about the position if they're not in it?
The developers have always done the interviewing of candidates at every place I've worked. We know exactly what to ask and what technical answers actually indicate they can get the job done. It's not hard to know what to ask when you actually do the job you're interviewing someone about.