Tulip (with mixed color petal) mania in late 17th century in Netherlands was the classic example of how something like tulip which do not have any intrinsic value or, stupid use case like- its mixed color petal looks royal high class in garden or even some believed would bring good luck, could explode in value just by the excitation of new buyer. People would exchange their one slave for one bouquet of tulip in extreme cases. Even bitcoin bubble was dubbed as modern tulip mania by traditionalist who did not understand block-chain in depth.
Well, if we revisit basic laws of economics- price is simply the function of supply and demand. That means- more the demand, more will be the price. So, demand can arise from two cases: first, demand created only because new buyer is excited simply so that he can sell at higher prices to new buyer without the entity being transacted offering any distinct use case. This is the whole fall trap of MLM or network marketing with entities of no distinct use case, which was the exact story with OneCoin. Though with entities of practical distinct use case, MLM or network marketing has nothing wrong with it because the product itself is providing some use case or value with its consumers ,and s/he do not have to re-sell it to gain value from it. Like MLM or network marketing scheme laid around some entity say, herbal medicine. So, the lesson here is: researching out the real use case of end entity or product itself is the way to find out whether whole market will eventually crash down or sustain eventually.