The names you cite have pretty good advice to give, but they also have obvious incentives for doing so. That is, they are all trying to sell something to aspiri

The names you cite have pretty good advice to give, but they also have obvious incentives for doing so. That is, they are all trying to sell something to aspiring entrepreneurs. As are you, judging from your website. For those who are not looking to sell books, invest in the next big thing, give lectures, or provide startup consulting, "work on the product" is about the most non-terrible piece of advice anyone could possibly give.