Why did China’s zero-Covid policy lead to workers fleeing an iPhone factory?

Earlier this week, workers broke out of Apple's largest iPhone assembly factory in China after a Covid outbreak forced staff to lockdown at the workplace.

Videos shared online showed about 10 people jumping a fence outside the plant, owned by manufacturer Foxconn, in the central city of Zhengzhou.

But how are Chinese people and businesses grappling with President Xi Jinping's rigid zero-Covid policy?