It's important to maintain Horizon and apply new releases on a regular basis (They are generally released quarterly). New Horizon releases are required to support new versions of Windows 10, introduce new functionality and bug/security fixes.
VMware Horizon 7 Documentation
Windows 10 Guest OS support FAQ for Horizon 7.x and 6.x (51663)
It's also important to maintain the Client, be it the Horizon Client or a zero client firmware for compatibility and bug/security fixes.
