People are your most expensive and your most valuable asset. Yet building a thoroughly motivated, truly competitive, winning team requires more insight than is possible through interviews and job reviews-ask any football manager (my favourite game).
Intelligence, skills, experience - these are matters of record but attitude, behaviour and how people relate - while they may seem to be subjective characteristics - are as much a matter of fact (They are measurable).
There is a system that minimizes subjectivity in assessing these and it guarantees consistent and objective analysis regardless of age, sex, race, culture and language. It is a system that even eliminates the bias of the interviewer her/himself.