Steve Blank

Blank spent 21 years inside eight startups — semiconductors, supercomputers, enterprise software — before retiring and asking why some of them worked. The Four Steps to the Epiphany, self-published from his teaching notes, became the founding text of modern entrepreneurship; Eric Ries took Blank's Berkeley class as a condition of Blank's investment in IMVU, and turned the ideas into the Lean Startup.

Blank is the root node of the modern startup canon. After eight startups in Silicon Valley's formative decades, he wrote down the heresy that became orthodoxy: startups are not small versions of large companies, and no business plan survives first contact with customers. Customer Development — get out of the building, test every hypothesis — spawned the Lean Startup through his student Eric Ries, reshaped how universities teach entrepreneurship via his Lean LaunchPad course, and even changed how the U.S. government commercializes science through the NSF I-Corps program built on his method.