The idea seems to be that it doesn't have to be the right idea, or a successful idea, but it does have to be an idea worth pursuing. If you don't have that, you'll just be spinning.
I guess an 'idea worth pursuing' needs to be good enough to overcome the fear associated with starting a startup. You need a strong belief in the idea if you have a lot of fear to overcome.
Maybe his point(1) is indirectly really about point(5) (for many of us)
