You should be following their lead. There is no reason to expect mentees to stick around for a long time if they can go command a meaningful salary and quality-

You should be following their lead. There is no reason to expect mentees to stick around for a long time if they can go command a meaningful salary and quality-of-life bump somewhere else. I understand the psychology around not putting more resources into your existing staff -- it's basically "why buy the cow when you're getting the milk for free?" -- but as long as this "5% per year is a great raise!" crap is going around, no one a) upper-mid-level or lower; with b) market value; and c) corresponding self-esteem; is going to stay in a specific job more than 2-3 years. There's no reason to expect anything else. If this is going to change, companies are going to have to start working hard to curb the "impulse buy" psychology at work in racing to get $BUZZWORDY_CANDIDATE_X. Despite this, there is great personal value in mentoring people. You learn a lot and establish a supportive substructure within the community. It's better to have your mentees move around. That way, they can throw you an escape line if you need it. People who stay at one company for too long end up with a rusty skillset and a heavily distorted perspective on how things operate. Companies may not notice it, but their cheapness is probably a much better thing for the goose than it is for the gander. Circulation is healthy.