A textile-yarn company in western Indian soon will have more machines than workers. A manufacturer in southern India sold almost double the number of its automated goods last year. India's biggest carmaker has one robot for every four plant employees.

Automation will double over the next three years in Indian factories, according to a survey by Willis Towers Watson. Companies in the Asia Pacific region reckon machines will account for 23 percent of work, on average, over the next three years, compared with 13 percent today. In India, that figure is expected to rise to almost 30 percent from 14 percent over the same period.

India Inc. is turning to machines quicker than its global peers. But unlike companies in Japan and Germany — which are automating to move up the food chain as their workers age — factories in the world's second most populous country have a surprising motivation: They're running out of willing (human) workers.

This is also happening as India's ballooning working-age population needs more jobs. Over the next decade, 138 million people will be added to the workforce, a 30-percent rise, according to the McKinsey Global Institute.

The trouble is finding jobs that Indians actually want. The country's workers would rather drive for food-delivery services on the breezy, albeit steamy, roads of Mumbai and work in hotels than in factories. Fair enough. Who would want to work in a yarn mill, which needs to maintain a temperature of 33 degrees Celsius (91 degrees Fahrenheit) and 60-percent relative humidity? Conditions on other industrial factory floors are likely worse.

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