This is self-perpetuating. It's been my experience that moving companies has gotten me +20% in pay for doing the same work with the same title. If employers assume people will leave after 2 years and hence don't give promotions and give paltry CoL raises then obviously why would people stay? So these employers won't give raises to their current workers but will happily give new employees +20% every 2 years just for swapping names on their Resume? Obviously something doesn't add up here.