A lot of projects carried out by ICO do not have a working product. And recently it's some kind of trend to collect money for future developments. I do not advise anyone to invest in such projects.
Actually this is really good suggestion and all people must follow this to avoid scam. I think we all dont want to get scam so try to follow the ico which only have working product. Recently many ico just want to raised money and just go away, with this experience now we need to start to avoid not working product ico.
Yes of course because invest to no product ICO is very worthless because it surely scam investment. So to avoid being scam make have research about the ICO, everything or all the details about it. Also if there's no product if ICO then have doubt to it because in one good project there's always a good product that you can see. And if your going to invest just put only small amount of your money so that there's only low risk.