Based on the team, the funding partners, the investors, the core behind the project. More such parameters contribute to the project. However even after analysing these many things we can see potential projects ending up as scams. This is ridiculous, and in some projects there'll be break in between.

The lack of development make the project go worse and finally after years once again it gets on track. Those weren't really scams, but lack of development or funding leads to some negative results on the market.