I think reworking the same champion several times shows...

That their kit is not healthy or that they are just not able to produce a kit with their theme that isn't impossible to balance. Biggest contenders would be rengar and nidalee. They both never get it right ever. Rengar is even worse now. Nidalee is an abomination. These two champions are like time bombs. Once they get buffed they will go off and be extremely strong to once being nerfed again. I think we should consider a new approach to champions like these.