If you don’t know the jewellery, know the jeweller. – Anon
An earnest MBA student once asked me for the secret to choosing the right interest rate to use in a discounted cash flow model. He was clearly agonising over this question. I wished I’d answered, "It’s always the humans!" Instead, I smiled politely and thought to myself, that’s not the right question. Yes, investing is a maths exercise. Price sensitivity is crucial. But because we’re looking into the future and trusting people to make good decisions on our behalf, we absolutely have to choose the right people and cultures.