People who make complains like this most of them rush into crypto just to make money very fast in crypto, they didn't make research to know about the coin they invested. When people go into crypto blindly it is either they went into the wrong investment that led them to be scammed. If people take their time to understand the investment they are going in their won't be much complains about scam and investing into the wrong coin.
It is necessary to investigate first because if we leave the project without knowing about it then we will regret in future when we see the success of people who invest in those projects. All projects are not scam and every project is not trustworthy therefore keep in mind that first know about the project to avoid regret in coming days.
Those who are expert can easily know about project so they can easily know that which project is scame and which is trustworthy because they read all the details according to projects and take a review of the whitepaper so they usually take an accurate decision.