…sure that there's exactly one service that manages each interface, so that they don't fight for ownership of the network device, trample on each other's feet and undo each other's settings.
To improve the situation in systemd v255 we introduced a udev property ID_NET_MANAGED_BY= which can be set on a network interface device. The value is expected to be a some string identifying the intended owning network management service, by convention in reverse domain name syntax.