Earlier, customers using SSO who wanted the groups in their IDP to be auto populated within Box, needed to contact Box support to enable this. With this feature, Box is now making this mapping process self serve, so customers can setup SSO much faster!
More details here: https://support.box.com/hc/en-us/articles/360043696514-Setting-Up-Single- Sign-On-SSO-for-Your-Enterprise.