Exactly. Many of these interviews it only takes one person to feel 'eh' or negative on the person to tank the candidate, so the more people you interview that person, the more likely you're going to have that impression on one of those people (especially if it's an all day series of interviews, you'll probably start to get mentally exhausted near the end of it), and the more likely any given candidate will be rejected.

It's the same principle behind using large numbers of disks in certain RAID configurations. If the pool can't tolerate a disk or two failing, adding more disks increases the chances of one or more failures occurring and tanking the pool.