Why are specific champion onslaught quests staggered?

I don't mind too much that the augment amounts are staggered since clearing the later tiers still clears the earlier tiers. Sure you'll have to repeat struggles but at least you do clear a mission for it. But why stagger a quest like "play only Ziggs and Sona" I get literally nothing for this, and will have to do it again later for myself.

My only thought is that you're trying to discourage as many people as possible from working together so that fewer people get the free stuff.