It's important to hire people with diverse experiences and viewpoints, which you don't necessarily get if you just hire straight-A Harvard MBAs. Getting good grades and having courage are not the same thing. Being really smart and having good judgment are not the same thing. No one should be winnowed out so early in life.
You're a product of your experience, so the fact that I came of age as an investor in the 1970s has basically made me scared of everything. I've found that abject fear and sound analysis can be a very healthy combination for an investor.