Final answer:
Conscientiousness is the Big Five personality dimension that is most strongly related to predicting job performance because it involves qualities pivotal to reliability and effectiveness in the workplace.
Step-by-step explanation:
The Big Five personality dimension that is most valuable for predicting job performance is conscientiousness. This dimension includes qualities such as organization, efficiency, competence, self-discipline, and achievement striving, making individuals who score high in conscientiousness more reliable and better performers in the workplace. Studies have found a robust positive correlation between conscientiousness and job performance across various occupations. Although other personality dimensions like extraversion and agreeableness can influence certain job outcomes, conscientiousness has been consistently identified as having the strongest relationship with overall job performance.