Because rich folks don’t want to attribute their fortune to being born rich, to being lucky by being in the right place at the right time, or shady dealings. It’ll always convince themselves it’s because they’re so hard working, such a genius, such great instincts for business… It doesn’t help that they’ll attract a bunch of yesmen and society at large respects money so much. From there on, they’ll Dunning–Kruger in spectaculair fashion over anything that strikes their fancy.

The real smart ones know this can happen and make sure to guard themselves against this. They other ones fire anybody with a different opinion until their luck runs out.