I would have thought most ICOs are scams because most AltCoins are crashcoins that peak a short time after release and then are gradually dumped. There may even be a few really big ones out there right now that will hurt a few people
But you can't expect every coins to be a success, to have a winner you must also have losers.
This is not true anymore, most of them has a trend which is definitely the reverse of your thoughts. They do an ICO, then their token hits the markets, exchanges. Then the price is dumped. And then it starts to rise once again. This is the benefit for the long term investors.