As a manager you should be doing your research to know the people behind the project,its not an excuse because you trusted the team behind it without knowing whos behind the development of the ICO that is a big bullshit !
Agreed, if a manager doesn't research his projects and it turns out that most of them are scams, it's at least negligence on his part and that qualifies as not being a good bounty manager. If a vendor sells spoiled food and people die because of it, he can't just shrug with his shoulders and walk away.