The original pokemon contests had beauty as their sole category, and developed out of arguments between poets and philosophers as to which pokemon were the most beautiful. It was hoped that with enough judges and a format based on combining aesthetic appeal with motion and function, and where type advantages were irrelevant, beauty could be determined not by photographers and arguments but by competition, much as battles determined power.
A few years after it had started, an elite coordinator shocked Hoenn by entering a Feebas, often considered the ugliest of pokemon species. Even more bizarrely, the Feebas managed to win. It was whispered for some time that the scoring rules rated beauty not by any overall metric, but relative to their species, or that the judges were bribed. Yet the rules, published soon after, said no such thing, and two new judges did not prevent the Feebas from repeating next year.
But the repeat sparked no accusations, for before the Feebas could be presented with its victory ribbon, it evolved into a Milotic; a pokemon thought at the time to be a myth. The beauty of this multicolored, sleek, and twirling pokemon had sparked dreams for generations, so if it evolved from Feebas, then Feebas could not be without beauty of their own.
The next year's contest was won by that Milotic, but it was the other, unorthodox contestants who captured the most attention. The story had grasped Hoenn's imagination, and trainers from near and far entered all sorts of pokemon never considered beautiful in the hopes of pulling off a surprise victory or discovering an evolution. None succeeded, and few of their techniques could be called beautiful, but the intelligence, toughness, cuteness, and coolness they displayed led to the diversification of pokemon contests into the five categories known today.