Gōngsī dǎobì, tā bèi bīshàng-liángshān, zhǐnéng zìjǐ chuàngyè.
The company went bankrupt and he was driven to desperate action; he had to start his own business.
Tips
history
From the Ming-dynasty novel 水浒传 ('Water Margin'). The hero Lin Chong (林冲) is repeatedly persecuted by a corrupt official until he flees up Mount Liang to join the outlaws, the archetypal 'good man pushed into outlawry' scene.
usage
Almost always passive: 被逼上梁山. Modern usage often softens to 'forced into a corner so you take a leap you wouldn't otherwise make', quitting a job to start a company, picking up a new skill out of necessity.