After decades of building and selling companies for billions, Kevin O'Leary has identified one common habit he believes is keeping millions of Americans poor.

"Shark Tank" investor Kevin O'Leary has a simple secret for staying motivated: he loves proving people wrong. "I just love it ...

O’Leary’s frustration stems from watching people miss the bigger picture of compound growth. When he sees someone spending $28 on lunch, he’s not just seeing one expensive meal.