Why do power plant recruiters consider the unit area of the power plant where employees have worked?

Newcomer's point of view ~ The bigger the unit, the higher the level of comprehensive automation and intelligence, the higher the quality of personnel and the more standardized the management. We are a 4 * 600,000 unit with two computers and one control, and there are departmental examinations every quarter. Each shift has value-added learning and simulator training, and the main and auxiliary are separated. Many equipment maintenance is the responsibility of manufacturers and contractors ~ This training will definitely have a deeper understanding of the system and a more global awareness ~ Will there be a relatively complete and scientific training assessment system? How can there be 5 million units? At present, 654.38+00,000 is the largest! And big companies don't want older employees, preferably about 40, technicians and engineers, so jumping to big companies is very promising ~