Bounty hunters are alwasy blame for selling their tokens so quickly without waiting for the project develpment as outline in the roadmap. I don't think bounty hunters are to blame because a lot of bounty hunters hold their coins for years.
To some extent yes. After working for several months for a project, when they collect payments, they seem to convert the tokens to fiat to solve their personal need but other times, private and presale investors and team who recieve huge amount off bonuses causes dump too