The IO, just like the other two assessors, is required to assess as to whether the candidate he is interviewing possesses the requisite 15 OLQs in adequate measure or not.
An IO tracks the life history of the candidate in front of him through his childhood, family and academic environment, the opportunities available, difficulties faced, successes and failures to construct a consistent behavioural profile.
A guiding principle for all IOs is: Past behaviour is indicative of future conduct; more consistent has been a past behaviour, more likely it is to be repeated in the future.