Sometimes this question is given by a well-prepared interviewer, but in my experience (on “both sides” of the interview), this question is usually asked by an UNprepared interviewer. S/He (the interviewer) hasn’t even read the applicant’s resume carefully and is killing time as S/He BEGINS to read it while the applicant answers.
Same goes for other cliched questions: Sometimes there’s a good, prepared interviewer asking it, but not usually.
A variation on the theme, meant to make the UNprepared interviewer SOUND prepared by implication, is, “Tell me something about yourself that’s not apparent from your resume.” I really hate these (although I had an answer ready). Dude? The reason stuff IS or IS NOT on my resume is because of what’s important to this job. Jeesh.
As an oft-unprepared interviewer, all I have to say about your spurious accusation is... Okay, you got me...
To me, this question has always just meant, “Go into your dance.” They don’t really care about learning the facts about yourself—the important ones are in the resume. What they want is to see how you express yourself, what your personality is like, and how you sell yourself. And whether you can deal with the ambiguity of an open-ended question.