Most people have absolutely no concept how much $1 billion is. So I use this example.
If you earn $50,000 a year, it would take you 20 years to earn $1 million. Now, you would not have $1 million at the end of 20 years, you would have earned that much.
$1 billion is $1 million times 1000. Therefore, if you earn $50,000 a year, to earn $1 billion would take you 20,000 years. That is not a typo. Twenty thousand years.
Now, consider Bezos has at least $150 billion. At the same $50,000 a year it would take you three million years to earn that much.