They may not say it, but it's quite obvious that essentials (housing, grocery, utilities, insurance, health care, etc.) take up a larger percentage of the income of someone at the median than of someone in the top 10%. It's also quite obvious that if you are supporting 4 people vs. 1, essentials will take up a much larger share of your income. It seems to me a lot of these gurus assume everyone is childless and making 6 figures.