At a point the team start given excuses to abide by what they promised to do or stop communicating with the community then I can sense the project is scam. How do you determine a project is gone bad and won't fulfil it promise? What criteria do you use ? or you wait for years thinking all will be well ?
Usually when the developer team is no longer active to communicate about the development of the project or the transaction volume is too small compared to the acquisition of ICO. Communication from the developer team is important because it is to ensure investor confidence.