The shortest answer I can give you is 'A rip-off'! I'm going to try and explain to you what they are and how they work to the best of my limited ability. The way a Multi Level Marketing scam works is that a company has a product which they have other people (not stores) sell. But there isn't much profit to be made in an individual selling the product, the only real profit is earned when new people who are recruited by current salespeople buy bulk 'starter kits' and recruit new people to buy kits also. This means people have to keep recruiting more and more people in their 'downline' in order for people further 'upline' to make money. If you put this all out on paper, the arrangement things all turns out suspiciously triangular . . .

Multi Level Marketing companies are EXTREMELY predatory. The target groups of people who are in need of money (young people, minorities, single parents- usually women) or desperate to make a living for themselves that doesn't involve being a wage slave. They make promises that can't be fulfilled- saying that enlisting to sell a product has the potential to earn someone a six figure income in a relatively short amount of time. Once the person purchases a starter kit / initial bulk order of the product, they soon realize the often overpriced product is incredibly difficult to sell. This leads the person to believe that they were the reason for their failure, and not the Multi Level Marketing system.