We can't know what he is thinking, but I can imagine him feeling stressed if he want's to maintain his life style has a few children and wants to retire very ea

We can't know what he is thinking, but I can imagine him feeling stressed if he want's to maintain his life style has a few children and wants to retire very early. It requires a big big nest egg to provide an income of around a million for the 50 or 60 years that either he or his wife will live after he stops working. Retiring in 15 years requires quite a bit of investment every year if he wants to roughly maintain income at retirement, and many people would hope to be better off over time. Depending on how much risk he is willing to take, he might need to invest as much as $400,000 per year! For such an early retirement he might be seeking an eventual portfolio of as much as $30,000,000 before he retires. Right now you can't count on much more than a couple of percent above inflation return on investments without taking risks that he might not be comfortable with.