The project developers should be able to clearly define the purpose of their project using simple and short sentences. If they are taking too much time and beating around the bush, then that either means: their agenda is not clear or they are hiding something. Both of which are not that encouraging scenarios.
Make sure that the developers are not anonymous. There should be 100% transparency when it comes to their names, business plans, locations etc. You should be able to contact them regarding any and all information that you need to get from them.
There should be a legal framework between the developers and the contributors including terms and conditions set for the ICO.
Lastly, and most importantly, you need to make sure that the ICO funds are being stored in an escrow wallet. An escrow wallet is basically a multi-sig wallet which needs multiple keys to be opened. One of those keys must be held by a neutral third party.
