I choose to work with every single person that I work with. That ends up being the most important factor. I don't interact with people I don't like or admire. That's the key. It's like marrying.
As I have mentioned before, we cannot make the same sort of money out of permanent ownership of controlled businesses that can be made from buying and reselling such businesses, or from skilled investment in marketable securities. Nevertheless, they offer a pleasant long term form of activity (when conducted in conjunction with high grade, able people) at satisfactory rates of return.
What an investor needs is the ability to correctly evaluate selected businesses. Note that word “selected”: You don't have to be an expert on every company, or even many. You only have to be able to evaluate companies within your circle of competence. The size of that circle is not very important; knowing its boundaries, however, is vital.
Of the billionaires I have known, money just brings out the basic traits in them. If they were jerks before they had money, they are simply jerks with a billion dollars.
Our marketable equities tell us by their operating results - not by their daily, or even yearly, price quotations - whether our investments are successful. The market may ignore business success for a while, but eventually will confirm it.
The value of market esoterica to the consumer of investment advice is a different story. In my opinion, investment success will not be produced by arcane formulae, computer programs or signals flashed by the price behavior of stocks and markets. Rather an investor will succeed by coupling good business judgment with an ability to insulate his thoughts and behavior from the super-contagious emotions that swirl about the marketplace.