(Reuters) - In the eight years since Zhang Shuxiang first left her village in the poor interior of central China, she worked in 20 factories before coming to the assembly line of a Foxconn plant making products for tech firms including Apple. She wants it to be her last.

The 26-year-old has worked in factories making products as varied as coffee makers, jewelry, Apple's LED screens and now computer motherboards. Each time, she quit, blaming low wages and unreasonable supervisors and joined yet another factory.

"Factory work is too tiring," she said when asked about life after Foxconn, which she plans to leave by June.

"Since last year, I've kept on telling myself I would never want to enter a factory ever again, but I'm still doing it in spite of myself."

She embodies the shifting expectations and opportunities of tens of millions of young Chinese workers from the countryside who have turned their country into a workshop of the world.