It was explained to me that born-in brothers have been observed over a larger space of time, their families as well, so must be "indoctrinated" better, ha.
Sometimes the only way new blood is brought in is by the hand of the WTS directly or through the CO, thinking that new blood will break up the family stranglehold. Some congregations develop 2 factions that battle and undercut any good idea even resisting the WTS and CO.
So the key is that when the BOEs resist the WTS, they try to break them up. If the suck up to the CO and WTS, all is good.
I knew an elder (regular pioneer) and his wife sent to a rural PA area to takeover. No one came to the KH for 2 months...just the 2 of them. The local jws would not return their phone call or when they came by. Finally the WTS sent a registered letter to the other elders saying if they did not turn up and cooperate, the congregation would be dissolved and the jws there would have to travel 60 miles one way to the nearest congregation. Only then did people start coming.