I guess fraudulent is not preventable but you can minimize being a victim if you will be very vigilant in your actions towards your investments. Doing more research before engaging to something which includes money will reduce the chances of being a victim of fraudulence.
knowledge is the best way to dodge fraud. and where ever you are, in any platform, there are many fraud that hunt ever person move. ask to someone that know about that thing, get more experience to make yourself expert, and sometime, you need to be victim to get more experience
Knowledge is power, if you have right knowledge you can easily avoid scam projects. People are becoming blind to rewards and that's why they keep losing in fraud projects. Remember that the scammers are becoming more intelligent than before and there are studies saying that the victims of the scammers are keep increasing because of the investors who doesn't have right and enough knowledge.