A next door neighbor at our previous home dealt in Amway and was apparently quite successful with it. He quite obviously had been at it for some time, and had at least a half-vast tribe of sub-tier dealers who trooped in and out regularly to pick up products and deliver "his cut." So far as I know he did no direct selling on his own (but may have still been recruiting).
My observations are that the products are, in most cases, of "usable" quality, if you're not too fussy about the results. It is extremely unlikely that a person can make more than "occasional pin money" from selling them, and only those who recruite lower tier sellers are likely to make even moderate income from the deal.
IF YOU ARE RECRUITED by anyone below the highest level, your recruiter's cut of your sales must pay his recruiter's cut of your sales, who must pay ... on up the line. As with any Ponzi scheme, the only ones who can possibly profit are those who got there first.
Except under unusual and very fortuitous conditions, you are not first in line.
One "analysis" a few years back derived the postulate that to have a net positive cash flow over a sustained period, each tier of a branch in an Amway "nework" must be a minimum of 30 to 40 percent larger than the tier above it. If your "recruiter" has recruited 50 people to work for him/her, you (and each of his other 49) will need to recruit at least 65 to work successfully for you. And to be successful for more than a very short term each of your 65 "workers" must recruit an additional 85 people to sell the stuff for them.
One might get by with fewer active "workers" but the drop-out rate for your "less successful" business will demand that you continually recruit new replacements for the ones who give up.
At the time, it appeared that this analyst had obtained fairly specific information about the Amway program, and in particular about their "revenue sharing" cuts and distributions. His calculations did appear to be "real math" and not just guesswork. (The article appeared in a "newsletter" from an established investment firm as advice on career planning, sent to me because they hadn't yet figured out that I had nothing to invest that met their minimum account restrictions.)
A second observation, without intent to be disparaging, was that about half the "agents" who visited my neighbor on Amway business appeared (in casual conversation) to be "intelligence impaired," although none were obviously dysfunctional in non-challenging situations. (I don't think I would have cared to try to explain even a very simple tax return to any of them, as they appeared unable to grasp much past "change for a quarter.") One must suspect that his recruits came mostly from "populations" he had identified as most easily recruited(?).
Unless you are peculiarly adapted to accepting what appears to me to be a "cult mentality" and being a "true believer," I'd think you'd be at least as well off renting a booth at the local flea market and raiding trash bins for something to sell.
But I've never believed that I'd be much of a saleperson, so I may have an odd view of it all.