there are very many of them to be honest, the issue is that people usually think having things explained in whitepaper means i will be successful which is not true no matter how hardworking a team is. i can categorically say that some determined team fail because of the kind of project they did as its complex and unrealistic so at some point they had to abandon it. the way and means by which a project idea can be realised  is more important if a project will last.