How did isolationism hurt China

Isolationism hurt China:

Isolationism is a policy in which the government limits its alliance with foreign countries when it comes to foreign policies and it also keeps distance from other countries affairs. China implemented isolationism in the 15th century when the Europeans were exploring resources and establishing colonies in various parts of the world.

China was also in exploration right about the same time but the mission was later abandoned due to isolationism and this reduced China's chances of establishing itself in other countries. China missed out on finding resources in foreign countries, gaining governmental control of over other countries which would have increased Chinese Power.