High employee turnover where staff come and go frequently, this tends to lead to an increase in spending as you will have to do more recruitment and training. High employment turnover can also indicate an issue internally such as management issues. While employees may have very good reasons to leave, too many can lead to a disruptive organisation.
It is sometimes possible to plan for turnover especially when someone resigns, is dismissed, is retiring or leaves due to ill health. The longer an employee works with a company the more likely they are to stay, so as a employer it will pay to focus on being aware of recruitment and training procedures.