[stygiansonic]

Agreed - the answer to this question is really the result of how much one thinks one knows. Because a little knowledge can result in false confidence, those that rate highly will fall into two categories: Those that actually know, and those that don't.

If the interviewer can distinguish between these two categories, then what value does the question add? If the interviewer cannot and is relying on the answer to this question (even partially), then it's an example of relying on a false signal.

Whenever I'm asked this question, I always respond with the following questions:

1) What does a "10" mean?

2) What does a "1" mean?

3) What's the difference between 5, 6 and 7?

4) (Optional, this could easily come across as being snarky) What's the range of levels in your team/org/dept for this metric?

[reagency]

You are absolutely right, but your behavior would offend the kind of person who thought it was a good question in the first place.

[doragcoder]

I would welcome the challenge in what rating is what. Because I know they are highly subjective. This is not an adversarial question, it's mainly used as an indicator to gauge where to direct the interview.

I like to interview people across a range of subjects (as I have not had the chance to hire a pure specialist). So knowing what they feel confident in answering will help me tailor the questions to what their perceived strengths are.

So I think it gives me a feel of your confidence level in a language. If you flipped through a "Teach yourself C++ in 24 hours" book once, then rate yourself a 10 on a scale from one to 10. Then not answering basic C++ questions will raise red flags.

If they answer a "1" on something. (And I re-assure them that answering 1 is perfectly ok). Then I can feel a lot more comfortable giving them more hints, or a lot more supporting detail in a question that they have indicated they are not very strong in.