Take Rodan+Fields, a skincare line developed by the dermatologists who created Proactive. It’s supposed be top-notch stuff. When they initially launched the product, they went the traditional retail route. Estee Lauder then bought the company for an undisclosed amount and continued to sell it through traditional retail. Sales of Rodan+Fields were surprisingly lackluster, however, so its former owners bought the company back and implemented the MLM model. Sales of the product skyrocketed to over a billion dollars. They’d claim it was thanks to the word-of-mouth marketing MLMs facilitate. I’d venture to guess it had more to do with the fact they have a captive customer base amongst the hundreds of thousands of distributors who are required to make minimum purchase amounts each month and recruit other distributors who will have to make minimum purchase amounts each month too.
I know there are a few companies, like Mary Kay and Lia Sophia, who have a generally positive image, but there are many more, often built around some investment scheme, which continue to give this sector a bad image. If you scan the Internet, you will find dozens of negative articles, like "What's Wrong With Multi-Level Marketing?", but very few singing their praises.