"Could not set STA to kernel driver"

I'm browsing my system log and have noticed that it is packed with this message:

Mon Oct 15 09:59:06 2018 daemon.notice hostapd: wlan0: STA b4:f6:1c:08:d2:ca IEEE 802.11: Could not set STA to kernel driver

The MAC address will vary. Nothing seems to be malfunctioning, so I'm planning to ignore it, but curious as to what that error message means.

some of your devices do not use full wifi capabilites (if any at all)