In simple neuroscience terms, 'fit' to a job means the individual is applying their most natural, instinctive preferences to the work. 'Fit' means the critical activities of the job are performed to a high standard for long periods of time. In this state the individual experiences motivation, satisfaction, is fully engaged,  with low stress: the perfect conditions for retention, which provides a solid career foundation for the individual, and greater productivity for the employer. 

This is the power of applied simple neuroscience, enabling precise job matching, setting-up for success; the right people in the right jobs, at scale.