Does the desktop client "poll" the local sync location when checking for changes?

I would like to create a sync connection in a desktop client which runs on my home server to sync all my pictures between my Nextcloud and some location on a NAS in my home network.

ATM, the drives of the NAS are most of the time in IDLE/standby state. Especially during the day when nobodies at home. This is good for disk health & lifetime and I’d like to keep it this way.

Therefore I’m worrying whether creating such a connection in the desktop client would prevent the target disks from going to sleep due to constant sync checks (polling), even if nothing has changed.

Is this something I need to worry about or does the client don’t need to “hit the network” for sync checks due to some internal indexing which is used for those checks etc.?