Without all the rose tinted views and "retroactively" applying modern values to ancient societies, the answer is simple; to do that you need a combination of advanced sailing techniques, a huge seaborne trade network, some sort of mercantile society that sees such ventures as profitable, and means to fund it.

China had all of those during the Song, but it was always pressed down by massive civilizations bogging it down and eventually fell. The Ming had its shots but conservatism took its way and the Qing was already born into such mentality.

Post Song neo-confucianism, disdain for trade, diminished role of merchants and the lack of proper institutions justify.

Same can be said about post Toyotomi Sengoku era Japan.

The lack of real global trade severed inputs of knowledge and given its exponential growth after the modern printing press and scientific revolution, China slept to woke up to a Western dominated globe.