set for life means not having to work a job.
Not having to work does not mean not working, it means that you have the freedom to take risk-free risks...
Let's say he takes the money plays with some of it (new car, puts aside money for a degree) and puts most of it in some sort of investment, and ends up with 100k a year after tax.
He's 19, he can now go out secure in the knowledge that any project he takes on will not ruin him.
Start a new company, go looking for venture capital, spend the year networking, new company fails?
Damn... oh well looks like he still has a solid enough income to just try again.
Spend the Summer chasing tail coming up with a new idea, try again in the winter, fail.
Try again in spring, oh this time it worked, made another load of cash.
Set for life does not, should not mean never working again, it means having such an amazing safety net that even when you fail you are still able to live well enough to try again with out the danger of losing you home, having trouble affording food, ending up back in your parents basement in your 30s.