That genius design quickly became known as the Cartier Santos, and it's widely recognized as the very first men's wristwatch. Before this, wristwatches were mostly seen as women’s accessories. The Santos completely flipped that script, showing everyone that a wrist-worn timepiece could be both practical and stylish for guys, too.

What started as a practical tool for a pioneering pilot soon evolved into an absolute icon and an everyday essential. It's a prime example of how some of the most enduring innovations often come from someone just trying to solve a personal problem, and in doing so, they end up revolutionizing an entire industry.