>I will totally appreciate the honesty and it goes a long way.
Not far enough to get a job in most cases, at which point, after the rejection, you and I are likely done and won't talk again. On the remote chance we cross paths again, the honesty might be worth another interview (if you're still in that position), but not much more. Person-to-person, I know the honesty is appreciated, but here's why candidates are not likely to be honest and simultaneously have no moral/ethical failing during interviews:
You're an agent of the company with a power dynamic over candidates when interviewing. You can't be honest with us via feedback, even if you wanted to, because there's potential legal problems for the company if you are. Many companies don't give feedback as policy for these reasons. So, knowing that I know that you can't be completely honest with me, I only hurt myself by being honest by telling you I've seen the problem before.
If I already knew the answer, but can't answer 'why?', then that's on me - I likely don't fully understand the solution in that case. Reject those people, sure. But they have no obligation to be honest with you. Similarly, if I already knew the answer and disclosed that fact, I might get a tougher question. So there is real a risk that I hurt my chances by being honest.
The risk of getting a tougher question is important. For it to be really fair, you'd have to grade these questions and determine if the next question is of similar difficulty. But your interview and problem grading process (if you have one) is not likely to be disclosed to me. The honesty would be appreciated, but we both know that interviewers aren't going to share those details chiefly because it defeats the purpose of the test, but also it'd end up on a forum if you're a well-known company leading to more cheating.
If you were giving a well-known test developed by professionals (GRE, GMAT, LSAT, SAT), there are significant resources to show me that those are fair tests developed by academics and other professionals. I would trust those testing admins to substitute questions of a similar difficulty. Were that the situation with your interview, the risk of getting a tougher question by being honest is significantly diminished because I know you have a bank of questions with accurate difficulties attached.
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I'm not arguing that you should change your process. A candidate unable to answer 'why?' is a perfectly good reason to say the candidate failed the question and maybe the interview. I'm arguing that this really shouldn't be considered cheating or a moral/ethical failure.
Not far enough to get a job in most cases, at which point, after the rejection, you and I are likely done and won't talk again. On the remote chance we cross paths again, the honesty might be worth another interview (if you're still in that position), but not much more. Person-to-person, I know the honesty is appreciated, but here's why candidates are not likely to be honest and simultaneously have no moral/ethical failing during interviews:
You're an agent of the company with a power dynamic over candidates when interviewing. You can't be honest with us via feedback, even if you wanted to, because there's potential legal problems for the company if you are. Many companies don't give feedback as policy for these reasons. So, knowing that I know that you can't be completely honest with me, I only hurt myself by being honest by telling you I've seen the problem before.
If I already knew the answer, but can't answer 'why?', then that's on me - I likely don't fully understand the solution in that case. Reject those people, sure. But they have no obligation to be honest with you. Similarly, if I already knew the answer and disclosed that fact, I might get a tougher question. So there is real a risk that I hurt my chances by being honest.
The risk of getting a tougher question is important. For it to be really fair, you'd have to grade these questions and determine if the next question is of similar difficulty. But your interview and problem grading process (if you have one) is not likely to be disclosed to me. The honesty would be appreciated, but we both know that interviewers aren't going to share those details chiefly because it defeats the purpose of the test, but also it'd end up on a forum if you're a well-known company leading to more cheating.
If you were giving a well-known test developed by professionals (GRE, GMAT, LSAT, SAT), there are significant resources to show me that those are fair tests developed by academics and other professionals. I would trust those testing admins to substitute questions of a similar difficulty. Were that the situation with your interview, the risk of getting a tougher question by being honest is significantly diminished because I know you have a bank of questions with accurate difficulties attached.
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I'm not arguing that you should change your process. A candidate unable to answer 'why?' is a perfectly good reason to say the candidate failed the question and maybe the interview. I'm arguing that this really shouldn't be considered cheating or a moral/ethical failure.