Originally posted by IluvMCAT
Though I agree that one can be rejected or put on hold for many reasons, I also think that it's possible, even likely, that schools intentionally waitlist applicants that they feel are overqualified. A school has absolutely no reason to accept an applicant that is likely to decline the offer. It would push their selectivity rating down. From their perspective, it's more prudent to offer you the waitlist and see what happens later in the year. If you're still interested in April, then they can give you a second look.
Why do you think they ask how many schools you applied to? They wouldn't ask unless they used this information. If you're "overqualified" and you tell them that you applied to 20 schools, then they are likely to think that you'll be heading elsewhere.