Employee turnover is a tremendous problem across the workforce. It drains resources and hurts morale. According to data drawn from 30 case studies and 11 research papers, it costs an organization at least 20 percent of the departing employee’s salary to find a replacement. However, when the departing employee was a good worker who liked her job, the impact can be even worse. So for organizations looking to maintain sustainable workforces, it’s important to understand the reasons good employees decide to leave. According to a survey conducted by Gallup last year, nearly 50 percent of the 7,200 adults polled said they had left a job to get away from a manager, but there are other, more nuanced reasons a good employee might decide to jump ship. Unnecessary rules is a major one. Unrealistic attendance policies, overbearing dress codes, and meaningless paperwork and oversight are all reasons employees may look elsewhere. It’s important for managers to realize they hired someone because she was skilled and capable, so it’s OK to trust her. Lack of personal and professional growth opportunities are also major factors in turnover. A smart manager will always look for ways to help employees use their skills and hone new ones.