The main problem with MLM is that it hires the sales ppl indefinitely without paying a fixed salary until the whole supply and demand chain collapses ( i'm referring to those highly aggressive type of MLM that requires members to buy products periodically to reach certain level ). When it does , many would lose their shirt , their family and friends while the owner and a few members at the top of the chain make a ton. I believe MLM is one of the most extreme form of capitalism which we should all be very very careful about ( or avoid like a plague
) .
I read an article that says playing slot machine has a better chance in winning than MLM .
Seach MLM scam in google or yahoo , you would get plenty of information pertaining to the subject.