Many a trader got scammed in recent years due to the fraudulent projects, no matter if they are ICOs, social media "gurus" or trading platforms. In my opinion, it would be important to first educate beginners (here's an article on how to avoid mistakes, scams included
https://www.cryptocointrade.com/education/avoid-cryptocurrency-trading-mistakes/). How do you figure one out and what can be done in near future to limit these frauds an access to the market?
There are some obvious signs that actually tells us whether an ICO is a scam or legit. First of all, look at the developers and the whole team. If they are well known developers, chances are low that they will be scamming. But this does not mean that all new developers are scammers. You should give them chances to prove themselves. As long as they are totally transparent with everything, you will be fine. Also if the project is a clone of another one, chances of the project not being successful is high. Just look for those obvious signals. The only to limit these frauds are to call them out and ignore them.