Best

The situation is simple for a genius. He has his own idea and does not discuss the problem with someone else. He make the decision, and things settle.

But, let's face it, if 20 idiots come together and discuss a problem, it is not the best opinion that would stand out - but the one made by the most outspoken (alas, maybe I should say loudspeaking) member.

What about if the decision is to be made by someone else?

First, let's assume this someone else, who is usually at a higher position, has no idea of himself. I must say that's not the most common scenario as it is highly probable that he is just another idiot. Otherwise he should have his own idea and made the decision already.

If he asks advise from a single genius, he should follow the advise and there's no problem what-so-ever.

But, once again, that's not usually the case - even if there is a genius sitting next to him all the time.

Alas, you imagine that much: If he asks opinion from a group of people and receives several different opinions, he will not pick the best suggestion - but the one make by the advisor with the most outstanding presentation skill.