I used to think discipline was a personality trait. You were either born with a "military mindset," or you were like me — a chaotic creative who relied on bursts of adrenaline to get things done. Then I watched my friend, Elena. On paper, Elena is arguably the laziest person I know. She hates stress. She refuses to rush. She doesn't do "crunch time." And yet, over the last year, she built a side business, learned a new language, and turned her health around completely. Meanwh