That's of course the best way to do it but many people like to hear a second opinion or maybe some simply don't have the time or will to do this research.
Thats why you need to find a trusted reviewer if you dont have time to do a research about a project your self. There is not hard to find someone, who you share an opinion with and trust his judgement.
Yes it is best suggested to do your own research in investment programs, you cannot held resposible to any news agency. I participated in a scam project which CoinTelegraph was paid to published. Any project can pay to publish in major news circles. So in the end we better rely on our own judgement
At the end everyone has to decide by themselves. Sometimes with smaller investment I just tried it. But in larger invests I did a long research that it is not a scam.