Danko and Stanley seem to see a glimpse of successful businesses when they suggest starting professional businesses. Such businesses tend to need to generate less revenue to make an equivalent level of profits. But this is equivalent to starting a business with high net margins. Such factors are discussed at length in my own book Thinking Like An Entrepreneur . The flaw of pursuing spending to show you are affluent and have financial status is very thoroughly trashed, as it rightfully should be.
All successful people tend to be achievement orientied.
Unfortunately, many academics measure success by the degrees you hold or the degree of knowledge to which you have been formally exposed. Because of this The Millionaire Next Door misses that there are many successful endeavors which do not demand eight-year degrees. You will sense a certain academic bias in the book toward pursuing education. Finally, there is some very interesting food for thought about how wealth will affect your children. We like this book a lot.