What makes some start ups succeed while others fail?

Is it: (a) Timing

(b) Ideas

(c) The Team

(d) Business Model

(e) Funding

It’s a big question, what makes some start ups succeed while others fail? Bill Gross has founded a lot of start-ups, and has gathered data from hundreds of companies, to rank each company on five key factors. He found one factor that stands out from the others.