Tánpàn shí tā yīn yī jù qìhuà fānliǎn, zhēnshì xiǎobùrěnzéluàndàmóu.
He turned on his partner over one angry remark during negotiations - truly, small impatience ruins great plans.
Tips
history
From 《论语·卫灵公》: 巧言乱德，小不忍则乱大谋. (Clever words disturb virtue; lack of forbearance in small things wrecks the great plan.) Confucius's warning against short-term emotion overriding long-term strategy.
usage
The 忍 here is 'to endure / hold back' - especially holding one's tongue or temper. Common in leadership and negotiation contexts, and in parents' advice to hot-tempered children.
