I'm going to keep developing this product unless I fail to hit clear benchmarks within the next two months that I've set with my quitting coach. - Annie Duke

The promise of this book is that if we follow the example of poker players by making explicit that our decisions are bets, we can make better decisions and anticipate (and take protective measures) when irrationality is likely to keep us from acting in our best interest.

To figure out whether a decision is good or bad, you need to know not just the things that might reasonably happen and what could be gained or lost, but also the likelihood of each possibility unfolding. That means, to become a better decision-maker, you need to be willing to estimate those probabilities.

this isn't what Levitt found. When he followed up with the coin flippers two and six months later, he discovered that for the big life decisions, people who quit were happier on average than people who stuck, whether they quit on their own or after the coin flipped in favor of quitting. While the decisions may have felt close to the people making them, they were not actually close at all. As judged by the participants' happiness, quitting was the clear winner. Because people were much happier when they quit what they considered a close decision, that shows that people are generally quitting too late.