What is the most important business skill? (Istanbul)

In terms of doing business globally, I am curious to know what is the most essential skill in business. Is it networking? A great money making idea? A dynamic sales strategy? How about an in depth knowledge of current market trends? The most successful people in history had a vision and took a chance. Sometimes I wonder if luck is just being at the right place at the right time. I've been reading some articles on people who had great ideas. but their ideas were stolen and they never got credit for them. Isn't that a kicker? I guess having a great idea is not enough. I am just curious to know your opinions on this and who your business icon is. My Icon is Zuckerberg.