Fame
If you're considering this career path, it's because you generally like the idea of being famous—or more specifically you like the idea of your designs being famous. You want the clothes or purses or shoes you come up with to make every fashionista's dreams come true.
Of course, the chances of you ever achieving fame as a fashion designer are smaller than that Brooklyn efficiency you'll be living in for a good chunk of time...but if others have gone from rags to riches in the fashion world, maybe you're thinking you can too.
Take Gabrielle "Coco" Chanel, one of the most influential fashion designers of all time—and not to be confused with Coco Puffs, one of the most influential cereals of all time.
Born to a single, very broke mother and raised in a convent, you could say she had some obstacles to overcome. Chanel's big break came when her Bohemian lifestyle led her to the dotage of several wealthy Parisians. And boy, did they dote.
Suddenly, Gabs had the money and freedom to design and make hats, which she sold out of a shop in Paris. Her style soon took off, with clients from around the planet wanting to cover their heads with whatever she was making (source).
Soon enough, Chanel began making clothes full-time and was famous and wealthy in her own right within just a few years. Today many of her contributions to fashion live on, including her famous perfume, the Chanel suit, suntans, and the famous "little black dress."
Oh, you didn't realize someone invented that? Now you know why everyone is cuckoo for Coco.