Turnover occurs when an employee leaves a company, usually voluntarily, and must be replaced. When turnover rates are high, it should be a signal to an employer that something might be wrong in the organization, such as below-market compensation, lack of flexible scheduling, poor job fit, inadequate training, lack of career growth, or poor supervision or management. Turnover costs include lost productivity, costs associated with hiring a new employee, the cost of temporary employees or overtime to cover the workload of the person who left the company, and training. Even more important may be the loss of skill, experience, and customer relationships associated with the resignation of a valuable employee.