How to tell what champion will be nerfed

First it was meow then it was super galaxy and now it is elchapo

Every favor of the month champ seems to get a new skin before getting nerfed to the dirt....whats next you say? http://na.op.gg/champion/missfortune/statistics/adc

https://www.youtube.com/watch?v=Y1xo6VO_rkg

https://memecrunch.com/meme/1TKNQ/i-rest-my-case/image.jpg?w=625&c=1