I think people make the mistake of thinking that 100% retention is even desirable. The company isn't paying me what I am _worth_, they are paying me what I am

I think people make the mistake of thinking that 100% retention is even desirable. The company isn't paying me what I am _worth_, they are paying me what I am _worth to them_. If my unique combination of skills is a better fit and more valuable to another company, then it is more worthwhile for me to move on and it is not worth my old company to pay me above what they can afford for the role. Plus some turnover and fresh ideas are always healthy. Just look at baseball teams. Could the Cleveland Guardians have paid Francisco Lindor what his market rate was? Maybe, but it would have blown up the budget for the rest of the team. So he was traded to New York for some cheaper, younger (and less skilled at present) players which fit the team's plan. Win-win in this case, obviously there are many bad examples too!