There is a large number of topics on Bitcointalk and sometimes it is very hard to distinguish a Scam from a non-Scam when there is no clear proofs.
Yes, in order to learn how to identify a scam project, we need to explore many topics. Of course, scammers will not give clear evidence. With experience we will have the intuition for this.
If it would be simple to identify a scam project, investors did not lose there money. Investors became more experience, but scammers become more experience too.