Do you need your money next year, or can you let it grow for a while? - Ramit Sethi

Most of us fall into one of two camps as regards our money: We either ignore it and feel guilty, or we obsess over financial details by arguing interest rates and geopolitical risks without taking action. Both options yield the same results — none.

The American Psychological Association reports that Americans today, compared to the 1950s, seem less happy, even though we eat out twice as much and own two times as many cars. We have so many more toys, like big-screen TVs, smartphones, and microwaves. But that isn't leading to a more satisfying life.

Marshall Goldsmith, one of the world's top executive coaches, put it to me this way: "Your biggest challenge [is] customer selection. You pick the right customer, you win. You pick the wrong customer, you lose. Focus on helping great people get better."