That's the investor techniques now, buy at presale and bonuses then sell when listed. But it is still risky to them in a way that they will need to research and get updates to know the project will succeed. Some cause of selling of Bounty hunters too.
not only knowing the project that will succeed. they must know and make sure they are not in a project scam, because it can eliminate their money. most investors also play when the first dump is registered in exchange. because they can get the price of coins much cheaper than the price of the pre cio.