When Rachel Tipograph joined Gap in 2012 as the retailer's youngest director of global digital and social media, she was 27, and the problem she was handed at the top level was legible but diffuse: Gap's relevance to its historical core customer — the 18-to-34-year-old urban woman — was declining in ways the company's own metrics did not cleanly explain.

Butterfield had founded a multiplayer gaming company called Tiny Speck that was building a game called Glitch.

Theranos promised a single finger-prick of blood could produce hundreds of diagnostic results.