Well the truth be told 80% of bounty hunters has a tendency to dump there tokens immediately when the project is listed on and exchange and a good number of that percentage are newbie in the cryptocurrency world. Also there are adverse effects of dumping because it reduces the price of the token and this can be annoying to investors and other rational bounty hunters
Actually there are some reasons why most bounty hunter dumped their tokens after listing because most of the ICO project are fake or scam. But of course not all, there are tokens that having great potential to growth and some hunters are keeping hold the tokens.