This document explains the effect of the Group Policy > Client Settings Manager > Mapped Drive Control > Always sync folder meta data when browsed by explorer setting.
By default, Always sync folder meta data when browsed by explorer is disabled. When off, Windows File Explorer will receive directory information from the CentreStack Windows Client's cache. The cache is updated in the background asynchronously via a notification from the server when files change. It is possible when the setting is off that the directory information is not 100% accurate as the cache may be stale on the CentreStack client. But as a user traverses the directory tree it will trigger the server to send cache updates to the client for each directory traversed. It may take some time for the client to be notified of the update from the server so the directory listing in File Explorer may remain stale until the notification is received.
With Always sync folder meta data when browsed by explorer enabled, the client will always request the latest directory information from the server for each directory traversed. This can make File Explorer directory listing more accurate but at the expense of added load on the client and server.
The recommendation is to leave this setting disabled unless you notice that the directory listing are often stale and impacting users. However, if the setting is enabled, then you run the risk of File Explorer appearing to hang if the server and client can't fulfill real time directory listings fast enough.