Opinions expressed by Entrepreneur contributors are their own. In 1995, Kevin Plank founded Under Armour after dreaming of a non-sweaty T-shirt while working out on his football team. The inspiration is classic startup fodder… but one year in, it wasn’t going so hot. Plank had $43,000 in personal debt after spending his life savings and $40,000 on credit cards to get the company off the ground. In its first year, Under Armour made a pithy $17k in sales. Fast-forward 15 years to 2010, and Under Armour saw its first billion-dollar sales year. At one point, the company had 26 consecutive quarters of 20% year-over-year revenue growth or more.