Why didn't that Zac nerf go out in the main patch when everyone would read it?

I was watching a stream today and there was a Zac player acting really weird every time he used his Q, the streamer became very angry with the Zac for failing to abuse an OP champion and apparently not knowing how to use his Q.

I see now from the patchnotes that a very quiet hotfix has gone out that reduced the range of Zac's second Q by 1/3. That seems like a huge change to go out in a hotfix both in the degree of the power that takes from him, and the size of the change to the game this is. I thought hotfixes were supposed to be relatively minor, safe changes that have no risk of ruining something in the game.

Changing a range changes how the champion spaces on the map, it changes how an ability feels, and it changes how a player will have to make decisions. Just the fact that most players will not catch the hotfix since they already read the patch notes and then go into games knowing how to play with a much longer range ability should have kept you from sending this change out. If you really needed to nerf Zac (you probably did) then it should have just been a damage or base stat nerf for now until a new patch would come out.