Bengaluru, Jan. 12 -- Almost a decade ago, Pranav Vempati knocked on the doors of nearly 40 venture capital (VC) firms, asking them to back a bet that would take years to pay off. Not one of them said yes. Vempati was building technology-powered prosthetic hands-devices that could mimic real hand movements and help people with limb issues regain everyday movement. But when he told investors that product development alone could take five years, the conversations often ended after the first meeting.

Undeterred, Vempati, founder of the Hyderabad-based deep-tech startup Makers Hive, turned to strategic angel investors, doctors, hospital heads and industry insiders, who understood the problem and the patience it would take to solve it.

It to...