Bounty and airdrop can not kill a project, only a bad project kill itself, get it straight, mate. Prices go low after bounty distributed, yes but that ain't the main reason for a project to die.
This is true it is not only the bounty participants who kills the project. Actually it's been discussed before and a lot of factors kills the project. There's also investors who do not have the trust and patience that able to sell their coins. Once a project is legitimate price will rise in the market.