People leave all the time, for all sorts of reasons, e.g. to get side-promoted, to work on something different, to get more money. I've seen the opposite of yo

People leave all the time, for all sorts of reasons, e.g. to get side-promoted, to work on something different, to get more money. I've seen the opposite of your thesis -- that people who have opportunities and actively work on their careers tend to change jobs often so whoever does not must be stagnating.