Inconsistency in Ninjago?

I had a couple of questions about Ninjago and hoped someone here could help me answer them. As we know Lloyd gives Kai, Zane, Cole and Jay their elemental powers, but every other elemental master just had their power, how? Why did Chen not need all elemental powers to turn his army into anacondrais? He gets every single elemental power that’s been established at this point, yet they add more elemental powers in later seasons such as wind, water and time 3.Why did all the elemental masters...