[BobWarfield]

Wealth is not revenue, it is income that comes about in abundance. To increase income either increase revenue or decrease expenses. It turns out that decreasing expenses is nearly risk free and is easier. Hence the Millionaires Next Door are good at that strategy. Not sure why this book is having a resurgence, but the other big point it made was the value of owning your own business versus working for someone else.

A close corrollary of the expense thing is to evaluate debt as an investment with a guaranteed return equal to the interest you're paying. Once you see it like that, it's very hard to argue against paying off all of your debt as quickly as possible. Those returns are hard to come by on the revenue side.