Industrial-organizational psychology studies behavior in work settings, including personnel psychology which helps with employee selection and assessment, organizational psychology which enhances the work environment, and human factors psychology. Achievement motivation, the drive to succeed, is key to performance more than innate ability. Engaged employees who are involved and satisfied in their work perform better. Effective managers harness employees' skills, set challenging goals, and choose a leadership style like task, social, or transformational leadership to motivate workers.