I'm not appreciated' is a common employee complaint. Try to create a 'family' atmosphere. Employees want to feel comfortable where they work. This is becoming increasingly important in the workplace and management should give it attention. Create a total package that will be hard to beat.
Employees leave when they are dissatisfied or see greener pastures.
If the grass is not greener they are less likely to jump ship. Make certain your employees see opportunity in your business. Lack of opportunity is a major cause of turnover. When an employee does leave do an exit interview. You may get some insight on how to improve your turnover.