I coach two legendary Canadians who were each on the Dragon's Den at different periods. They both understand the theatrical nature of the show, it's underlying silliness and the inherent limitations that accomplished rich people have in picking winners. Most of the Dragons actually did relatively few deals for this reason. The cost of type I errors (investing in something dumb–a "false positive") is usually less than missing a truly good opportunity (a type II error, or "false negative"), except when it isn't. This bias is built into the human decision making calculus where, in primitive homo sapiens, false positives lead often to death and a halt of that particular DNA.