I don't think administrators have a "quota" of a certain
number of people they must interview. Generally speaking we
do a paper screen and select the best candidates "on paper"
-- I will say that I generally narrow it down to between 6 and
8 candidates, and each one has an equal shot at convincing me
that he or she is the best candidate for the job.
If you have had 7 interviews that tells me that you must look
good on paper. You may, however, need work on your
interviewing skills. Keep track of the kinds of questions
you are asked and reflect on how you might improve your
responses. After getting your "thanks for interviewing, but
you weren't the successful candidate" letter or call, you
might speak with the principal and ask how you could improve
on your interview -- just to get an idea of what might have
knocked you out of the running
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