Employee resignations of any type can have an impact on the efficiency and productivity of your workforce. Managerial resignations tend to leave a larger void due to the added responsibility a manager takes on. But the effects of employee resignations on productivity should be understood by company management so that measures can be taken to improve employee retention.
Morale suffers in a couple of ways when an employee resigns. If the employee was well-liked, then that positive portion of the workplace environment is gone, and that will have a negative effect on morale and productivity. But another way in which morale and productivity are effected by employee resignation is the curiosity that causes rumors about an employee leaving. If it was a key employee, an employee with a lot of tenure or an employee that was well-liked, then the rumors regarding her departure could lead to other resignations that will continue to affect productivity.
An employee that has been with the company long enough to become proficient in his job becomes a profit center for the company. Once that employee resigns, that experience is lost to the company. There is a gap between the moment the employee resigns and the time when the replacement employee is up to speed that has a significant effect on employee productivity. That gap of time will vary depending on the company and the kind of job, but it can affect the company's bottom line in any case.
An employee resignation means that the remaining employees need to find a way to make up for the departing employee's job while a replacement is recruited. Spreading out a workforce to cover an employee resignation means that it takes longer to answer customer calls, it can take longer to process customer requests and customers will not get callbacks on the status of their issue in a timely manner. Productivity drops as employees scramble to maintain a good level of customer service.
Managers that resign their jobs are leaving behind working relationships with their employees that will take months for a new manager to re-create. A manager understands her staff and knows how to get the most out of employees. When that manager leaves, the staff loses some of its motivation and must wait for the new manager to become comfortable in his position. As the entire department readjusts to the new manager, productivity will suffer.