Why go back to BO1?
I thought BO3 was fine. The rest of the world thought to, so why change it back to the old outdated BO1?
The rest of the world in competitive League use BO3, but garbage NALCS and EULCS had to be different. You tried BO2 in EULCS which failed, so you changed it to BO3, now back to BO1.
We'll have to see how the NALCS and EULCS goes.
But the moral of the story is: If it ain't broke don't fix it. WTF is wrong with you Riot?