Because you dont gain points for holding zones. Or you get minimal gains from it. Like defender kill bonus points. But just holding a zone doesn't constantly feed you tho. The team gets that strength of the wolf score bonus sometimes but thats it. Control tallies points earned by your team in a match. Capping a point gives eveyone in the zone points for the capture. And thats it. So if your team caps 2 zones with solo captures, and the other team just goes TDM and kills you guys, you lose. This very poorly explained in game tho