With exit intent, you can trigger a popup or other display type to show when it appears a visitor is leaving your site based on their mouse movement towards the back button or tab closing button.
The purpose of this exit intent pop-up is to make sure that they really want to leave your website. Confirming their intent will make them rethink the process and might even convince them to stay and continue to browse.
If you include discounts with this popup you might be able to do more than just convince them to stay.