Summary: <p>Dollar Shave Club and its hilarious marketing. Casper mattresses popping out of a box. Third Love’s lingerie designed specifically for each woman’s body. Warby Parker mailing you five pairs of glasses to choose from. You’ve seen their ads. You (or someone you know) use their products. Each may appear, in isolation, as a rare David with the bravado to confront a Goliath, but taken together they represent a seismic shift in a business model that has lasted more than a century.</p>
