I get a red signal when the price at PRE-ICO is quite very low, couple with high bonus allocated to investors compare to the price at ICO, also the team involve in the project must be traseable with verifiable good past track record
For sure team work is very important and they must have well determination about future of crypto as our entire investment is on their shoulders, so if the market of any ICO project gets red zone, we should invest as it needs small amount of money to be there but whenever you leave you will be able to make huge profit, the only rule is buy red and sell high.