I personally know and have worked with a few people who manage hedge funds (with a combined hundreds of millions in AUM). So fun fact: one of the tight-lipped secrets about the hedge fund industry (which could arguably also be said for a lot of the financial industry) - is that none of them actually know what they're doing.

Characters like Ackman, Shkreli, etc all sell the idea that they know what they're doing, when the reality is it's simply gambling with other people's money with minimal risk. Luck will favor some, and others...not so much. The entire industry is essentially a collective delusion/sham.