What would be the success rate of an individual, who lets say is smart but not a genius (maybe top 5% in SAT score, for example) that has a reasonable idea he came up with (that probably would not work out the way it is, but he doesn't know it yet) and has a successful entrepreneur advising him (perhaps a meeting once a month or so), and this individual would just not give up no matter what for, say, 5 years? As in, when he'll fail, he'll just try something else following his creativity and independent thinking, working hard and trying to move as fast as he can (although maintaining normal life to an extent, maybe weekly soccer and socializing a bit with friends and partner).

What are his chances of being a millionaire by the end of 5 year period? 50%? 90%? 20%? What do you think?