In the Three Kingdoms Period, Zhuge Liang lived in seclusion in a thatched cottage. Liu Bei, hearing that Zhuge Liang was very knowledgeable and capable, went to visit him, taking gifts, hoping that Zhuge Liang would agree to assist him with statecraft. He had to make three visits before Zhuge Liang agreed to do so, impressed by his sincerity. From then on, Zhuge Liang helped Liu Bei with all his heart, and made great achievements in both the military and political spheres.
This idiom means persisting with sincerity.