I still distinctly remember when a highly regarded colleague on our team resigned.  It was a few years ago at another company but the impacts of them leaving were were vast.  We knew we were losing a dynamic member who could motivate the group, steer the management team to adopt new ways we could sell our products in unique ways without affecting margins but in simple terms it felt like the Sales & Marketing gang would never be the same.

For managers and their business, it is great to keep check on how your staff contribute to the company but importantly how staff affect the performance of your teams, the culture or diversity.  One or all of these impacts may lead to a few or a landslide of departures and it pays to spot check or implement ways to #retain the ones you wish to keep.