Most entrepreneurs are understandably very possessive about their ideas because they believe that this is their magic sauce . They have been told that the heart of being an entrepreneur is being innovative , and that successful startups are those which can commercialize a new idea.
Entrepreneurs are focussed on converting their idea into a successful business, which is why they are very reluctant to share it with other people because they are scared that someone else will steal it.
However, this creates lots of problems. For one thing, you fall in love with the idea because it's yours, and you're not willing to listen to some of the deficiencies or limitations which it may have.