Literature Reference: 铅刀磨尽不成锋。——《喜与韦左丞同入南省因叙旧以赠之》 The lead knife, though worn down, never becomes sharp. Source from 'Xi Yu Wei Zuo Cheng Tong Ru Nan Sheng Yin Xu Jiu Yi Zeng Zhi' by Bai Juyi.
磨: Tempering. Honing.
尽: It signifies giving one's all and striving to the utmost, akin to exerting every ounce of effort and dedication.
Meaning: Worn down yet persevering, symbolizing resilience and relentless effort.