If a manager fails at employee retention, the chances are good that the manager has been unable or unwilling to develop their ability to manage and value people across the board. Managers who exhibit a pattern in which their key employees leave your organization cannot retain their management role.If you have fairly and ethically provided the manager the learning opportunities suggested here, you can, in good conscience, remove the individual from the managerial role. My experience has been that most managers consider this such a loss of prestige and face that they voluntarily leave the organization.