What do you think of defi projects, most of them are only good for the short term.To make a big profit, we must enter at the right moment, if we are wrong we will lose very deeply.
If that's their classification then we can compare them to Ponzi scheme, this is how Ponzi scheme works, you have to enter at the right time, if you failed to do so, you will end up losing it's an early bird thing, the early bird catches the early worms, but unfortunately on this kind of project, you never know when the scheme will end it could be the day after you invest or week.
Ponzi are automatic scam while De-Fi projects are not, at least some of them are not scam, the pump and dump situation was only brought by the hype of the De-Fi projects, but it will be stable overtime IMO.