As far as i remember, the chinese empire was toppled by a small fast changing merchant nation on a island half way around the world. Beginning a hundred years were it was trampled by repeatedly including by another island nation nearby.
The roman empire died the strangest death of all, it created such a tremendous underclass stagnant in misery (slaves, woman, all non-citizens) that a religion could basically overwrite its whole culture, erasing it from existence, without leaving behind even the technological advances.
China is on its way to become a superpower again. One could argue that the last 150 years are merely a temporary dip.
So many before them, were to take the throne for all eternity, the japanese, the koreans and then they all became just another part of a connected world and on the throne remained, he who could in-cooperate change the fastest and most efficient.
But every year changed may be as well. For example the November-revolution in Russia. There are numerous examples that change was for the worse, especially for the masses.
And the Chinese or Roman empires outperformed any other quickly changing empire by far.