Before I answer, you should know a few things about me. I've paid to get into a couple of Network-Marketing/Multi-Level-Marketing franchises, and I made a little money in it. I have worked in financial sales. I since went on to get my Masters in Business Administration. I've been there, and I know it in theory and practice. There's room for some nuance here, but for the most part:
Don't do it!
There's no snake oil out there that people can't get on their own. If you can sell it to them, then here's the simple case against it: if you're a good enough salesman to get other people to buy franchises from you (and really, you don't care about product sales, you care about franchise sales, because that's how they sold it to you, right?) you can make far more money selling business to business.
If you're a good enough sales manager that you can get good salespeople to buy franchises from you and sell more franchises, you'll make far more money managing salespeople selling business to business.
For the most part, people aren't good at sales, and that likely includes you. Most MLM's are sales groups with bad salespeople leading bad salespeople. It's the blind leading the blind. And as your friends get burned, and your family gets burned, and you start losing everyone who got burned, you'll start to wish you had never done this stuff in the first place.
Exceptions to the rule:
The main reason the above holds true is that the people involved in MLM don't really create any value. They're looking to get a free ride on everyone else in the pyramid beneath them. There are exceptions, the main ones that come to mind are like Mary Kay, where, ok, mostly women, makeup artists teach women how to apply makeup without looking like a clown, and it's a skill, and it's part of how they create value. And it may well be the best option for someone whose chosen career is a makeup artist.
At the age of 17, I sold books door-to-door in Southern Mississippi, mostly to teach myself how to talk to people, since I had grown up with my nose in a book. It turned out that the business was structured like a MLM to encourage salespeople to become managers, but I had no interest in that, I just wanted to learn people skills. I blew a couple hundred bucks on franchise fees on other MLMs, mostly because friends were in it.
Sales is hard work. Teaching people how to sell is even harder, and impossible if you don't know how. If you're good at it, you'll do so much better in a business to business setting. Think about the economics of it. Salespeople get paid on volume of sales. Businesses have a lot more money than consumers. You have to sell to an awful lot more consumers than businesses to make the same amount of money.
Think about competition, too. Considering Amway? You're competing with everyone from Walmart to the corner convenience store, and you will be asking everyone and their brother to join up. And many of them have already been pitched it, if they've been around long enough. The bargaining strength of your customers and suppliers is pretty strong. You have immense direct competition and product substitutes, and anyone else can go into the same business as you. Your competitive position is extremely weak. It's almost guaranteed to fail.
Don't do it!