Many students also like to ask "which JC should I go? should I pursue the college that is top in sports since i love sports or should i pursue the college that tops in academic?"
The root of these kind of questions are really simple. Get the student to search his soul on what he wants really. When a greed takes over, then everything becomes complex since everything looks so appealing.
Focus on one thing and work on one thing whole heartedly, whether business or PhD. When you are focus on one thing, pursue it with all your heart and don't look back, don't think of "what if i fail? what if i choose wrongly?". Once you have decided, "cross the river", "burn all boats, dont look back" and move forward. Its really that simple in life.
If you really should "fail", its not bad too because you would have learn valuable and important lessons. Its really the journey that matters and not so much on the end product. That way, you would not have lived your life in vain. Phd or business, we cant bring fame or fortune to our graves, so do they really matter?