The part of Harper’s job that is most demotivating is the lack of her work/life balance.  She mentions it a couple times and even to her colleagues at work as one of the reasons she is planning on leaving.  Its one of but not the only reason for her wanting to leave.  If I was the HR manager working with David, I would implore him to communicate more with Harper and have a more open-door policy.  Another way he could improve would be to give Harper her credit when it’s due by telling her she is doing a good job and even rewarding her for her hard work with some vacation time to cut through the long hours she puts in.  Another way David could help would be to talk about a promotion of some kind, Harper is taking on more work than before and has been in the same position for four years.  Harper could assume the role her previous supervisor Jose had, she is qualified enough.  Finding a way to cut down on her workload to achieve a better work life balance is crucial so David could facilitate more work to other team members to lighten Harpers load or hire another team member to balance out the assigned work.  Losing Harper would be shameful and could cause more people to leave.  You would have to hire a new person and train them for a role that someone has been doing for years.