Essentially: It is not common for doctors to be asked to locate the interviewer's mouth, ears and thumbs. If an interviewer asked that kind of thing, you'd really have to suspect that he couldn't tell a good doctor from a bad one.
But programming interviewers do need to ask this kind of thing. So you really have to suspect…
The problem isn't that we're asking doctors to locate their mouth, ears, and thumbs.
The problem is that the resume and candidate pipeline is so crappy, that the interviewer cannot be sure if the person sitting across the table is a doctor, or a plumber, or a carpenter, or an accountant, or maybe a bum off the street.
My interviewing life would be a lot easier if there was a firm guarantee that every candidate knows at least basic programming - and by basic I mean basic - i.e., can put together a for loop that compiles, in a language of their choice.
The second part of this problem is that the industry has so many jobs where the absolutely clueless can survive that "X years experience" in-industry is not a trustworthy metric for competence. "5 years at County General" for a MD, with a clean record, is a pretty decent guarantee that your candidate is in the ballpark. "5 years at Accenture" for a programmer guarantees nothing, not even the ability to write FizzBuzz.
Elsewhere in the thread someone mentioned being incensed that, even with his years of experience, he was being asked elementary questions. That's why - years of working experience is not a valid signal for competence.
"5 years at County General" for a MD, with a clean record, is a pretty decent guarantee that your candidate is in the ballpark."
Scary but true: There are plenty of experienced doctors who couldn't pass a medical Fizzbuzz. My supervisor at my last teaching hospital, who has been treating patients for at least five years, failed the Fizzbuzz question I asked him. ("What's that other class of antibiotics you can't give patients with penicillin allergies?", if you're wondering.)
(There's also a few stories of people faking medical licenses and working as doctors for years before anyone noticed [1], but those are probably too rare to worry about.)
But programming interviewers do need to ask this kind of thing. So you really have to suspect…