The fact is that we are advertising agents nothing more. We ourselves often dont know what we are promoting. But this is just advertising and we are not insured against scam. No matter how much time you spend on studying a project, there is a risk that this is a scam.
To this we must take it easier for us it is just a job.
Yes, no matter how you study and research a certain project, there is no guarantee that you will not be scammed. That is why the best way is to participate in bounties where the payment/rewards are escrowed for assurance.