If you see that the project teams are getting less active in their social media, especially in their official telegram group. It is the sign that the project is probably scam/fake. You must avoid buying the tokens/coins from the project like that. It has a big chance to be dead coins/tokens. Also, if you see that the project has bad planning, roadmap, or the ideas in Whitepaper. It is not a good sign for quality project, it may be a fake one.