No entrepreneur wants to hear this, but one of the biggest reasons companies fail is because of the entrepreneur. There is a term, "founder's disease" that investors like to use, and it refers to an entrepreneur who already knows everything, thinks he's got it all figured out, and has a business plan that he thinks will work. However, there are real problems -- and he won't listen to anyone because he already knows everything and has it all figured out.

These types are uncoachable and won't take advice from anyone. They have a plan and they are going to stick to it no matter what. Also, they tend not to want to share in success because they are so sure their idea is going to make them millions, perhaps even billions.

How can you spot one of these people? They don't like hard questions about their company, they get defensive when you ask them such questions, they dismiss competition and don't treat it seriously, and they can't understand why you won't put money into their company right now.

When I deal with entrepreneurs, I like to push them a bit or be a little rude because I want to see if they give me attitude. If so, that's pretty much a clear indication that they have founders disease. Investors will never put money into such a company because they almost always fail.