The idiom Bai3 Fa1 Bai3 Zhong4 is a Chinese version of “A Hundred Shots, a Hundred Bull’s Eyes” . Here is a story of where it came from.

During the Spring and Autumn Period (770-476 BC), there was an expert archer in the state of Chu named Yang Youji. To test his skill, a person selected three leaves at different heights on a willow tree, and labeled them Leaf A, B and C. Yang was challenged to hit the leaves in order. Staying more than one hundred paces away, Yang Youji did hit the three leaves in order.

This idiom describes brilliant marksmanship. Later it indicates perfect precision and assurance.