Yet more advice given from the narrow scope of one person's experience. The problem is, some of it is just wrong. Some people have succeeded despite (or perhaps because of) just being in it for the money.
I think whether or not you're in it for the money ultimately doesn't matter very much.
What matters is how much value you create -- and it so happens that you create the most REAL value when you focus on other people's problems and solve them.
Solve other people's problems, create value, get paid, and as a result, solve your own problems.
Being in it for the money means you have to be in it for other people, ultimately. Well, at least the good kind of value creation. You could also just sell subprime mortgages and make a bucket load of money too, but we know where that ends up...
Actually I think the guy's correct in that it helps. I've seen this for sure in startups. I just think he's incorrect in that it's necessary, or that it should be a defining characteristic of an entrepreneur.
