That's very interesting, and a contrary norm to many big companies in the U.S. Companies here are happy to pay whatever it takes to fill an empty position, but they often have limits on pay raises that prevent loyal employees from getting fair pay as they gain skills and rise to higher levels of responsibility in the company. Many people enjoy the familiarity and relationships at their job and would rather accept being underpaid than be forced to take a new job every couple of years, so the company loses a few people but gets to keep the rest at below market rate. Loyalty is effectively punished, and job-hopping is how you keep your salary current with the market and your experience.

I know several people who have been affected by this, but the most dramatic was a software engineer at AT&T who had started in an entry-level position in network operations. He had received the maximum allowed raise every year, but he was being paid less than 70% of what other software engineers at the same level were making. The request to make a one-time adjustment to his salary had to be escalated to an executive in another office hundreds of miles away (the VPs in our office did not have enough authority) and took months to process. It was not routine at all. It involved a physical sheet of paper with the executive's signature on it.