One day Jobs marched into the cubicle of Larry Kenyon, the engineer who was working on the Macintosh operating system, and complained that it was taking too long to boot up. Kenyon started to explain why reducing the boot-up time wasn’t possible, but Jobs cut him off. “If it would save a person’s life, could you find a way to shave 10 seconds off the boot time?” he asked. Kenyon allowed that he probably could. Jobs went to a whiteboard and showed that if five million people were using the Mac and it took 10 seconds extra to turn it on every day, that added up to 300 million or so hours a year—the equivalent of at least 100 lifetimes a year. After a few weeks Kenyon had the machine booting up 28 seconds faster. - getpocket.com