Are you sure that all 10 of those devices are Z-Wave? (They could be ZigBee or LAN devices if you don't know. Only Z-Wave devices will show here, which last time I checked did show all of them.)
In general, the Z-Wave Settings page is not one you'll need to explore very often. If you just added new Z-Wave devices (or moved one a significant distance), you may want to do a "Repair." See more here: How to Build Your Z-Wave Mesh
Otherwise, there's really only a reason to go there for special circumstances--e.g., to put the hub in "general Z-Wave exclusion mode" to help exclude a device paired to another hub that wasn't properly removed and you want to use with Hubitat (Hubitat-paired devices can be removed from the device page itself), the above repair feature, or if you want to do something unusual like disable the Z-Wave radio for some reason (I did on my "test hub" because I don't use it). Official documentation is sparse but located here: Z-Wave Details - Hubitat Documentation
This isn't something I'd mess around with unless you have a reason to, however. Even a "repair," as nice as that sounds, is something I'd only do if you need to.
