Billionaires are almost always created by starting with substantial familial wealth, taking large financial risks, and getting lucky. They then generally misattribute this luck to personal excellence, causing them to underestimate future risks.
On the other hand, they also induce institutions to change in ways that really do insulate them as a class from the consequences of risk. Both of these factors would tend to reduce their fear of losing their wealth and status.
The day the Chicxulub asteroid hit.
Whichever day of the week it was, the subsequent 3.4 billion weeks have not yet balanced out the score.